diff --git a/firewall/inspection/inspection.go b/firewall/inspection/inspection.go
index 55629b19..7dc59494 100644
--- a/firewall/inspection/inspection.go
+++ b/firewall/inspection/inspection.go
@@ -85,11 +85,11 @@ func RunInspectors(conn *network.Connection, pkt packet.Packet) (network.Verdict
 			verdict = network.VerdictDrop
 			continueInspection = true
 		case BLOCK_CONN:
-			conn.SetVerdict(network.VerdictBlock)
+			conn.SetVerdict(network.VerdictBlock, "", nil)
 			verdict = conn.Verdict
 			activeInspectors[key] = true
 		case DROP_CONN:
-			conn.SetVerdict(network.VerdictDrop)
+			conn.SetVerdict(network.VerdictDrop, "", nil)
 			verdict = conn.Verdict
 			activeInspectors[key] = true
 		case STOP_INSPECTING:
diff --git a/firewall/master.go b/firewall/master.go
index 86196e36..cafd11f2 100644
--- a/firewall/master.go
+++ b/firewall/master.go
@@ -143,9 +143,6 @@ func DecideOnConnection(conn *network.Connection, pkt packet.Packet) { //nolint:
 		}
 	}
 
-	var result endpoints.EPResult
-	var reason string
-
 	if p.PreventBypassing() {
 		// check for bypass protection
 		result, reason := PreventBypassing(conn)
@@ -160,6 +157,9 @@ func DecideOnConnection(conn *network.Connection, pkt packet.Packet) { //nolint:
 		}
 	}
 
+	var result endpoints.EPResult
+	var reason endpoints.Reason
+
 	// check endpoints list
 	if conn.Inbound {
 		result, reason = p.MatchServiceEndpoint(conn.Entity)
@@ -168,10 +168,10 @@ func DecideOnConnection(conn *network.Connection, pkt packet.Packet) { //nolint:
 	}
 	switch result {
 	case endpoints.Denied:
-		conn.Deny("endpoint is blacklisted: " + reason) // Block Outbound / Drop Inbound
+		conn.DenyWithContext(reason.String(), reason.Context())
 		return
 	case endpoints.Permitted:
-		conn.Accept("endpoint is whitelisted: " + reason)
+		conn.AcceptWithContext(reason.String(), reason.Context())
 		return
 	}
 	// continuing with result == NoMatch
@@ -180,7 +180,7 @@ func DecideOnConnection(conn *network.Connection, pkt packet.Packet) { //nolint:
 	result, reason = p.MatchFilterLists(conn.Entity)
 	switch result {
 	case endpoints.Denied:
-		conn.Deny("endpoint in filterlists: " + reason)
+		conn.DenyWithContext(reason.String(), reason.Context())
 		return
 	case endpoints.NoMatch:
 		// nothing to do
diff --git a/intel/block_reason.go b/intel/block_reason.go
new file mode 100644
index 00000000..5a14c6cd
--- /dev/null
+++ b/intel/block_reason.go
@@ -0,0 +1,51 @@
+package intel
+
+import (
+	"fmt"
+	"strings"
+)
+
+// ListMatch represents an entity that has been
+// matched against filterlists.
+type ListMatch struct {
+	Entity        string
+	ActiveLists   []string
+	InactiveLists []string
+}
+
+func (lm *ListMatch) String() string {
+	inactive := ""
+	if len(lm.InactiveLists) > 0 {
+		inactive = " and in deactivated lists " + strings.Join(lm.InactiveLists, ", ")
+	}
+	return fmt.Sprintf(
+		"%s in activated lists %s%s",
+		lm.Entity,
+		strings.Join(lm.ActiveLists, ","),
+		inactive,
+	)
+}
+
+// ListBlockReason is a list of list matches.
+type ListBlockReason []ListMatch
+
+func (br ListBlockReason) String() string {
+	if len(br) == 0 {
+		return ""
+	}
+
+	matches := make([]string, len(br))
+	for idx, lm := range br {
+		matches[idx] = lm.String()
+	}
+
+	return strings.Join(matches, " and ")
+}
+
+// Context returns br wrapped into a map. It implements
+// the endpoints.Reason interface.
+func (br ListBlockReason) Context() interface{} {
+	return map[string]interface{}{
+		"filterlists": br,
+	}
+}
diff --git a/intel/entity.go b/intel/entity.go
index e46ac041..8d2e21fb 100644
--- a/intel/entity.go
+++ b/intel/entity.go
@@ -16,43 +16,6 @@ import (
 	"golang.org/x/net/publicsuffix"
 )
 
-// ListMatch represents an entity that has been
-// matched against filterlists.
-type ListMatch struct {
-	Entity        string
-	ActiveLists   []string
-	InactiveLists []string
-}
-
-func (lm *ListMatch) String() string {
-	inactive := ""
-	if len(lm.InactiveLists) > 0 {
-		inactive = " and in deactivated lists " + strings.Join(lm.InactiveLists, ", ")
-	}
-	return fmt.Sprintf(
-		"%s in activated lists %s%s",
-		lm.Entity,
-		strings.Join(lm.ActiveLists, ","),
-		inactive,
-	)
-}
-
-// ListBlockReason is a list of list matches.
-type ListBlockReason []ListMatch
-
-func (br ListBlockReason) String() string {
-	if len(br) == 0 {
-		return ""
-	}
-
-	matches := make([]string, len(br))
-	for idx, lm := range br {
-		matches[idx] = lm.String()
-	}
-
-	return strings.Join(matches, " and ")
-}
-
 // Entity describes a remote endpoint in many different ways.
 // It embeddes a sync.Mutex but none of the endpoints own
 // functions performs locking. The caller MUST ENSURE
diff --git a/nameserver/nameserver.go b/nameserver/nameserver.go
index a30d933c..9b3d8016 100644
--- a/nameserver/nameserver.go
+++ b/nameserver/nameserver.go
@@ -278,7 +278,7 @@ func handleRequest(ctx context.Context, w dns.ResponseWriter, query *dns.Msg) er
 
 		result, reason := conn.Process().Profile().MatchEndpoint(conn.Entity)
 		if result == endpoints.Denied {
-			conn.Block("endpoint in blocklist: " + reason)
+			conn.BlockWithContext(reason.String(), reason.Context())
 			returnNXDomain(w, query, conn.Reason)
 			return nil
 		}
@@ -286,7 +286,7 @@ func handleRequest(ctx context.Context, w dns.ResponseWriter, query *dns.Msg) er
 		if result == endpoints.NoMatch {
 			result, reason = conn.Process().Profile().MatchFilterLists(conn.Entity)
 			if result == endpoints.Denied {
-				conn.Block("endpoint in filterlists: " + reason)
+				conn.BlockWithContext(reason.String(), reason.Context())
 				returnNXDomain(w, query, conn.Reason)
 				return nil
 			}
diff --git a/network/connection.go b/network/connection.go
index e0af4c01..bbc088dc 100644
--- a/network/connection.go
+++ b/network/connection.go
@@ -31,9 +31,10 @@ type Connection struct { //nolint:maligned // TODO: fix alignment
 	Entity  *intel.Entity // needs locking, instance is never shared
 	process *process.Process
 
-	Verdict  Verdict
-	Reason   string
-	ReasonID string // format source[:id[:id]] // TODO
+	Verdict       Verdict
+	Reason        string
+	ReasonContext interface{}
+	ReasonID      string // format source[:id[:id]] // TODO
 
 	Started          int64
 	Ended            int64
@@ -164,59 +165,82 @@ func GetConnection(id string) (*Connection, bool) {
 	return conn, ok
 }
 
-// Accept accepts the connection.
-func (conn *Connection) Accept(reason string) {
-	if conn.SetVerdict(VerdictAccept) {
-		conn.Reason = reason
+// AcceptWithContext accepts the connection.
+func (conn *Connection) AcceptWithContext(reason string, ctx interface{}) {
+	if conn.SetVerdict(VerdictAccept, reason, ctx) {
 		log.Infof("filter: granting connection %s, %s", conn, conn.Reason)
 	} else {
 		log.Warningf("filter: tried to accept %s, but current verdict is %s", conn, conn.Verdict)
 	}
 }
 
-// Block blocks the connection.
-func (conn *Connection) Block(reason string) {
-	if conn.SetVerdict(VerdictBlock) {
-		conn.Reason = reason
+// Accept is like AcceptWithContext but only accepts a reason.
+func (conn *Connection) Accept(reason string) {
+	conn.AcceptWithContext(reason, nil)
+}
+
+// BlockWithContext blocks the connection.
+func (conn *Connection) BlockWithContext(reason string, ctx interface{}) {
+	if conn.SetVerdict(VerdictBlock, reason, ctx) {
 		log.Infof("filter: blocking connection %s, %s", conn, conn.Reason)
 	} else {
 		log.Warningf("filter: tried to block %s, but current verdict is %s", conn, conn.Verdict)
 	}
 }
 
-// Drop drops the connection.
-func (conn *Connection) Drop(reason string) {
-	if conn.SetVerdict(VerdictDrop) {
-		conn.Reason = reason
+// Block is like BlockWithContext but does only accepts a reason.
+func (conn *Connection) Block(reason string) {
+	conn.BlockWithContext(reason, nil)
+}
+
+// DropWithContext drops the connection.
+func (conn *Connection) DropWithContext(reason string, ctx interface{}) {
+	if conn.SetVerdict(VerdictDrop, reason, ctx) {
 		log.Infof("filter: dropping connection %s, %s", conn, conn.Reason)
 	} else {
 		log.Warningf("filter: tried to drop %s, but current verdict is %s", conn, conn.Verdict)
 	}
 }
 
-// Deny blocks or drops the link depending on the connection direction.
-func (conn *Connection) Deny(reason string) {
+// Drop is like DropWithContext but does only accepts a reason.
+func (conn *Connection) Drop(reason string) {
+	conn.DropWithContext(reason, nil)
+}
+
+// DenyWithContext blocks or drops the link depending on the connection direction.
+func (conn *Connection) DenyWithContext(reason string, ctx interface{}) {
 	if conn.Inbound {
-		conn.Drop(reason)
+		conn.DropWithContext(reason, ctx)
 	} else {
-		conn.Block(reason)
+		conn.BlockWithContext(reason, ctx)
 	}
 }
 
-// Failed marks the connection with VerdictFailed and stores the reason.
-func (conn *Connection) Failed(reason string) {
-	if conn.SetVerdict(VerdictFailed) {
-		conn.Reason = reason
+// Deny is like DenyWithContext but only accepts a reason.
+func (conn *Connection) Deny(reason string) {
+	conn.DenyWithContext(reason, nil)
+}
+
+// FailedWithContext marks the connection with VerdictFailed and stores the reason.
+func (conn *Connection) FailedWithContext(reason string, ctx interface{}) {
+	if conn.SetVerdict(VerdictFailed, reason, ctx) {
 		log.Infof("filter: dropping connection %s because of an internal error: %s", conn, reason)
 	} else {
 		log.Warningf("filter: tried to drop %s due to error but current verdict is %s", conn, conn.Verdict)
 	}
 }
 
+// Failed is like FailedWithContext but only accepts a string.
+func (conn *Connection) Failed(reason string) {
+	conn.FailedWithContext(reason, nil)
+}
+
 // SetVerdict sets a new verdict for the connection, making sure it does not interfere with previous verdicts.
-func (conn *Connection) SetVerdict(newVerdict Verdict) (ok bool) {
+func (conn *Connection) SetVerdict(newVerdict Verdict, reason string, ctx interface{}) (ok bool) {
 	if newVerdict >= conn.Verdict {
 		conn.Verdict = newVerdict
+		conn.Reason = reason
+		conn.ReasonContext = ctx
 		return true
 	}
 	return false
diff --git a/profile/endpoints/endpoint-any.go b/profile/endpoints/endpoint-any.go
index 34fd65b4..8e8deb98 100644
--- a/profile/endpoints/endpoint-any.go
+++ b/profile/endpoints/endpoint-any.go
@@ -8,8 +8,8 @@ type EndpointAny struct {
 }
 
 // Matches checks whether the given entity matches this endpoint definition.
-func (ep *EndpointAny) Matches(entity *intel.Entity) (result EPResult, reason string) {
-	return ep.matchesPPP(entity), "matches *"
+func (ep *EndpointAny) Matches(entity *intel.Entity) (EPResult, Reason) {
+	return ep.match(ep, entity, "*", "matches")
 }
 
 func (ep *EndpointAny) String() string {
diff --git a/profile/endpoints/endpoint-asn.go b/profile/endpoints/endpoint-asn.go
index dee94f2d..6713d199 100644
--- a/profile/endpoints/endpoint-asn.go
+++ b/profile/endpoints/endpoint-asn.go
@@ -16,24 +16,22 @@ var (
 type EndpointASN struct {
 	EndpointBase
 
-	ASN    uint
-	Reason string
+	ASN uint
 }
 
 // Matches checks whether the given entity matches this endpoint definition.
-func (ep *EndpointASN) Matches(entity *intel.Entity) (result EPResult, reason string) {
-	if entity.IP == nil {
-		return Undeterminable, ""
-	}
-
+func (ep *EndpointASN) Matches(entity *intel.Entity) (EPResult, Reason) {
 	asn, ok := entity.GetASN()
 	if !ok {
-		return Undeterminable, ""
+		return Undeterminable, nil
 	}
+
 	if asn == ep.ASN {
-		return ep.matchesPPP(entity), ep.Reason
+		asnStr := strconv.Itoa(int(ep.ASN))
+		return ep.match(ep, entity, asnStr, "IP is part of AS")
 	}
-	return NoMatch, ""
+
+	return NoMatch, nil
 }
 
 func (ep *EndpointASN) String() string {
@@ -48,8 +46,7 @@ func parseTypeASN(fields []string) (Endpoint, error) {
 		}
 
 		ep := &EndpointASN{
-			ASN:    uint(asn),
-			Reason: "IP is part of AS" + strconv.FormatInt(int64(asn), 10),
+			ASN: uint(asn),
 		}
 		return ep.parsePPP(ep, fields)
 	}
diff --git a/profile/endpoints/endpoint-country.go b/profile/endpoints/endpoint-country.go
index 63d21bfc..85449cf5 100644
--- a/profile/endpoints/endpoint-country.go
+++ b/profile/endpoints/endpoint-country.go
@@ -19,19 +19,16 @@ type EndpointCountry struct {
 }
 
 // Matches checks whether the given entity matches this endpoint definition.
-func (ep *EndpointCountry) Matches(entity *intel.Entity) (result EPResult, reason string) {
-	if entity.IP == nil {
-		return Undeterminable, ""
-	}
-
+func (ep *EndpointCountry) Matches(entity *intel.Entity) (EPResult, Reason) {
 	country, ok := entity.GetCountry()
 	if !ok {
-		return Undeterminable, ""
+		return Undeterminable, nil
 	}
+
 	if country == ep.Country {
-		return ep.matchesPPP(entity), "IP is located in " + country
+		return ep.match(ep, entity, country, "IP is located in")
 	}
-	return NoMatch, ""
+	return NoMatch, nil
 }
 
 func (ep *EndpointCountry) String() string {
diff --git a/profile/endpoints/endpoint-domain.go b/profile/endpoints/endpoint-domain.go
index 2691ba13..fbd0dcf9 100644
--- a/profile/endpoints/endpoint-domain.go
+++ b/profile/endpoints/endpoint-domain.go
@@ -28,47 +28,48 @@ type EndpointDomain struct {
 	Domain        string
 	DomainZone    string
 	MatchType     uint8
-	Reason        string
 }
 
-func (ep *EndpointDomain) check(entity *intel.Entity, domain string) (EPResult, string) {
+func (ep *EndpointDomain) check(entity *intel.Entity, domain string) (EPResult, Reason) {
+	result, reason := ep.match(ep, entity, ep.Domain, "domain matches")
+
 	switch ep.MatchType {
 	case domainMatchTypeExact:
 		if domain == ep.Domain {
-			return ep.matchesPPP(entity), ep.Reason
+			return result, reason
 		}
 	case domainMatchTypeZone:
 		if domain == ep.Domain {
-			return ep.matchesPPP(entity), ep.Reason
+			return result, reason
 		}
 		if strings.HasSuffix(domain, ep.DomainZone) {
-			return ep.matchesPPP(entity), ep.Reason
+			return result, reason
 		}
 	case domainMatchTypeSuffix:
 		if strings.HasSuffix(domain, ep.Domain) {
-			return ep.matchesPPP(entity), ep.Reason
+			return result, reason
 		}
 	case domainMatchTypePrefix:
 		if strings.HasPrefix(domain, ep.Domain) {
-			return ep.matchesPPP(entity), ep.Reason
+			return result, reason
 		}
 	case domainMatchTypeContains:
 		if strings.Contains(domain, ep.Domain) {
-			return ep.matchesPPP(entity), ep.Reason
+			return result, reason
 		}
 	}
-	return NoMatch, ""
+	return NoMatch, nil
 }
 
 // Matches checks whether the given entity matches this endpoint definition.
-func (ep *EndpointDomain) Matches(entity *intel.Entity) (result EPResult, reason string) {
+func (ep *EndpointDomain) Matches(entity *intel.Entity) (EPResult, Reason) {
 	if entity.Domain == "" {
-		return NoMatch, ""
+		return NoMatch, nil
 	}
 
-	result, reason = ep.check(entity, entity.Domain)
+	result, reason := ep.check(entity, entity.Domain)
 	if result != NoMatch {
-		return
+		return result, reason
 	}
 
 	if entity.CNAMECheckEnabled() {
@@ -80,7 +81,7 @@ func (ep *EndpointDomain) Matches(entity *intel.Entity) (result EPResult, reason
 		}
 	}
 
-	return NoMatch, ""
+	return NoMatch, nil
 }
 
 func (ep *EndpointDomain) String() string {
@@ -93,7 +94,6 @@ func parseTypeDomain(fields []string) (Endpoint, error) {
 	if domainRegex.MatchString(domain) || altDomainRegex.MatchString(domain) {
 		ep := &EndpointDomain{
 			OriginalValue: domain,
-			Reason:        "domain matches " + domain,
 		}
 
 		// fix domain ending
diff --git a/profile/endpoints/endpoint-ip.go b/profile/endpoints/endpoint-ip.go
index 6fa742c0..43ea47f7 100644
--- a/profile/endpoints/endpoint-ip.go
+++ b/profile/endpoints/endpoint-ip.go
@@ -10,19 +10,19 @@ import (
 type EndpointIP struct {
 	EndpointBase
 
-	IP     net.IP
-	Reason string
+	IP net.IP
 }
 
 // Matches checks whether the given entity matches this endpoint definition.
-func (ep *EndpointIP) Matches(entity *intel.Entity) (result EPResult, reason string) {
+func (ep *EndpointIP) Matches(entity *intel.Entity) (EPResult, Reason) {
 	if entity.IP == nil {
-		return Undeterminable, ""
+		return Undeterminable, nil
 	}
+
 	if ep.IP.Equal(entity.IP) {
-		return ep.matchesPPP(entity), ep.Reason
+		return ep.match(ep, entity, ep.IP.String(), "IP matches")
 	}
-	return NoMatch, ""
+	return NoMatch, nil
 }
 
 func (ep *EndpointIP) String() string {
@@ -33,8 +33,7 @@ func parseTypeIP(fields []string) (Endpoint, error) {
 	ip := net.ParseIP(fields[1])
 	if ip != nil {
 		ep := &EndpointIP{
-			IP:     ip,
-			Reason: "IP is " + ip.String(),
+			IP: ip,
 		}
 		return ep.parsePPP(ep, fields)
 	}
diff --git a/profile/endpoints/endpoint-iprange.go b/profile/endpoints/endpoint-iprange.go
index 16afa4bb..bc0d22fe 100644
--- a/profile/endpoints/endpoint-iprange.go
+++ b/profile/endpoints/endpoint-iprange.go
@@ -10,19 +10,18 @@ import (
 type EndpointIPRange struct {
 	EndpointBase
 
-	Net    *net.IPNet
-	Reason string
+	Net *net.IPNet
 }
 
 // Matches checks whether the given entity matches this endpoint definition.
-func (ep *EndpointIPRange) Matches(entity *intel.Entity) (result EPResult, reason string) {
+func (ep *EndpointIPRange) Matches(entity *intel.Entity) (EPResult, Reason) {
 	if entity.IP == nil {
-		return Undeterminable, ""
+		return Undeterminable, nil
 	}
 	if ep.Net.Contains(entity.IP) {
-		return ep.matchesPPP(entity), ep.Reason
+		return ep.match(ep, entity, ep.Net.String(), "IP is in")
 	}
-	return NoMatch, ""
+	return NoMatch, nil
 }
 
 func (ep *EndpointIPRange) String() string {
@@ -33,8 +32,7 @@ func parseTypeIPRange(fields []string) (Endpoint, error) {
 	_, net, err := net.ParseCIDR(fields[1])
 	if err == nil {
 		ep := &EndpointIPRange{
-			Net:    net,
-			Reason: "IP is part of " + net.String(),
+			Net: net,
 		}
 		return ep.parsePPP(ep, fields)
 	}
diff --git a/profile/endpoints/endpoint-lists.go b/profile/endpoints/endpoint-lists.go
index b11da060..27ec8b00 100644
--- a/profile/endpoints/endpoint-lists.go
+++ b/profile/endpoints/endpoint-lists.go
@@ -12,18 +12,19 @@ type EndpointLists struct {
 
 	ListSet []string
 	Lists   string
-	Reason  string
 }
 
 // Matches checks whether the given entity matches this endpoint definition.
-func (ep *EndpointLists) Matches(entity *intel.Entity) (result EPResult, reason string) {
-	entity.LoadLists()
-
-	if entity.MatchLists(ep.ListSet) {
-		return ep.matchesPPP(entity), entity.ListBlockReason().String()
+func (ep *EndpointLists) Matches(entity *intel.Entity) (EPResult, Reason) {
+	if !entity.LoadLists() {
+		return Undeterminable, nil
 	}
 
-	return NoMatch, ""
+	if entity.MatchLists(ep.ListSet) {
+		return ep.match(ep, entity, ep.Lists, "filterlist contains", "filterlist", entity.ListBlockReason())
+	}
+
+	return NoMatch, nil
 }
 
 func (ep *EndpointLists) String() string {
@@ -36,7 +37,6 @@ func parseTypeList(fields []string) (Endpoint, error) {
 		ep := &EndpointLists{
 			ListSet: lists,
 			Lists:   "L:" + strings.Join(lists, ","),
-			Reason:  "matched lists " + strings.Join(lists, ","),
 		}
 		return ep.parsePPP(ep, fields)
 	}
diff --git a/profile/endpoints/endpoint.go b/profile/endpoints/endpoint.go
index b634b911..43741c40 100644
--- a/profile/endpoints/endpoint.go
+++ b/profile/endpoints/endpoint.go
@@ -11,7 +11,7 @@ import (
 
 // Endpoint describes an Endpoint Matcher
 type Endpoint interface {
-	Matches(entity *intel.Entity) (EPResult, string)
+	Matches(entity *intel.Entity) (EPResult, Reason)
 	String() string
 }
 
@@ -24,6 +24,35 @@ type EndpointBase struct { //nolint:maligned // TODO
 	Permitted bool
 }
 
+func (ep *EndpointBase) match(s fmt.Stringer, entity *intel.Entity, value, desc string, keval ...interface{}) (EPResult, Reason) {
+	result := ep.matchesPPP(entity)
+	if result == Undeterminable || result == NoMatch {
+		return result, nil
+	}
+
+	return result, ep.makeReason(s, value, desc)
+}
+
+func (ep *EndpointBase) makeReason(s fmt.Stringer, value, desc string, keyval ...interface{}) Reason {
+	r := &reason{
+		description: desc,
+		Filter:      ep.renderPPP(s.String()),
+		Permitted:   ep.Permitted,
+		Value:       value,
+	}
+
+	r.Extra = make(map[string]interface{})
+
+	for idx := 0; idx < int(len(keyval)/2); idx += 2 {
+		key := keyval[idx]
+		val := keyval[idx+1]
+
+		r.Extra[key.(string)] = val
+	}
+
+	return r
+}
+
 func (ep *EndpointBase) matchesPPP(entity *intel.Entity) (result EPResult) {
 	// only check if protocol is defined
 	if ep.Protocol > 0 {
diff --git a/profile/endpoints/endpoints.go b/profile/endpoints/endpoints.go
index 7a49a0c8..d8af9423 100644
--- a/profile/endpoints/endpoints.go
+++ b/profile/endpoints/endpoints.go
@@ -21,6 +21,12 @@ const (
 	Permitted
 )
 
+// IsDecision returns true if result represents a decision
+// and false if result is NoMatch or Undeterminable.
+func IsDecision(result EPResult) bool {
+	return result == Denied || result == Permitted
+}
+
 // ParseEndpoints parses a list of endpoints and returns a list of Endpoints for matching.
 func ParseEndpoints(entries []string) (Endpoints, error) {
 	var firstErr error
@@ -57,7 +63,7 @@ func (e Endpoints) IsSet() bool {
 }
 
 // Match checks whether the given entity matches any of the endpoint definitions in the list.
-func (e Endpoints) Match(entity *intel.Entity) (result EPResult, reason string) {
+func (e Endpoints) Match(entity *intel.Entity) (result EPResult, reason Reason) {
 	for _, entry := range e {
 		if entry != nil {
 			if result, reason = entry.Matches(entity); result != NoMatch {
@@ -66,7 +72,7 @@ func (e Endpoints) Match(entity *intel.Entity) (result EPResult, reason string)
 		}
 	}
 
-	return NoMatch, ""
+	return NoMatch, nil
 }
 
 func (e Endpoints) String() string {
diff --git a/profile/endpoints/reason.go b/profile/endpoints/reason.go
new file mode 100644
index 00000000..d137c3b3
--- /dev/null
+++ b/profile/endpoints/reason.go
@@ -0,0 +1,34 @@
+package endpoints
+
+// Reason describes the reason why an endpoint has been
+// permitted or blocked.
+type Reason interface {
+	// String should return a human readable string
+	// describing the decision reason.
+	String() string
+
+	// Context returns the context that was used
+	// for the decision.
+	Context() interface{}
+}
+
+type reason struct {
+	description string
+	Filter      string
+	Value       string
+	Permitted   bool
+	Extra       map[string]interface{}
+}
+
+func (r *reason) String() string {
+	prefix := "endpoint in blocklist: "
+	if r.Permitted {
+		prefix = "endpoint in whitelist: "
+	}
+
+	return prefix + r.description + " " + r.Value
+}
+
+func (r *reason) Context() interface{} {
+	return r
+}
diff --git a/profile/profile-layered.go b/profile/profile-layered.go
index edb8a8a2..45311662 100644
--- a/profile/profile-layered.go
+++ b/profile/profile-layered.go
@@ -204,12 +204,12 @@ func (lp *LayeredProfile) DefaultAction() uint8 {
 }
 
 // MatchEndpoint checks if the given endpoint matches an entry in any of the profiles.
-func (lp *LayeredProfile) MatchEndpoint(entity *intel.Entity) (result endpoints.EPResult, reason string) {
+func (lp *LayeredProfile) MatchEndpoint(entity *intel.Entity) (endpoints.EPResult, endpoints.Reason) {
 	for _, layer := range lp.layers {
 		if layer.endpoints.IsSet() {
-			result, reason = layer.endpoints.Match(entity)
-			if result != endpoints.NoMatch {
-				return
+			result, reason := layer.endpoints.Match(entity)
+			if endpoints.IsDecision(result) {
+				return result, reason
 			}
 		}
 	}
@@ -220,14 +220,14 @@ func (lp *LayeredProfile) MatchEndpoint(entity *intel.Entity) (result endpoints.
 }
 
 // MatchServiceEndpoint checks if the given endpoint of an inbound connection matches an entry in any of the profiles.
-func (lp *LayeredProfile) MatchServiceEndpoint(entity *intel.Entity) (result endpoints.EPResult, reason string) {
+func (lp *LayeredProfile) MatchServiceEndpoint(entity *intel.Entity) (endpoints.EPResult, endpoints.Reason) {
 	entity.EnableReverseResolving()
 
 	for _, layer := range lp.layers {
 		if layer.serviceEndpoints.IsSet() {
-			result, reason = layer.serviceEndpoints.Match(entity)
-			if result != endpoints.NoMatch {
-				return
+			result, reason := layer.serviceEndpoints.Match(entity)
+			if endpoints.IsDecision(result) {
+				return result, reason
 			}
 		}
 	}
@@ -239,7 +239,7 @@ func (lp *LayeredProfile) MatchServiceEndpoint(entity *intel.Entity) (result end
 
 // MatchFilterLists matches the entity against the set of filter
 // lists.
-func (lp *LayeredProfile) MatchFilterLists(entity *intel.Entity) (endpoints.EPResult, string) {
+func (lp *LayeredProfile) MatchFilterLists(entity *intel.Entity) (endpoints.EPResult, endpoints.Reason) {
 	entity.ResolveSubDomainLists(lp.FilterSubDomains())
 	entity.EnableCNAMECheck(lp.FilterCNAMEs())
 
@@ -249,10 +249,10 @@ func (lp *LayeredProfile) MatchFilterLists(entity *intel.Entity) (endpoints.EPRe
 			entity.LoadLists()
 
 			if entity.MatchLists(layer.filterListIDs) {
-				return endpoints.Denied, entity.ListBlockReason().String()
+				return endpoints.Denied, entity.ListBlockReason()
 			}
 
-			return endpoints.NoMatch, ""
+			return endpoints.NoMatch, nil
 		}
 	}
 
@@ -262,11 +262,11 @@ func (lp *LayeredProfile) MatchFilterLists(entity *intel.Entity) (endpoints.EPRe
 		entity.LoadLists()
 
 		if entity.MatchLists(cfgFilterLists) {
-			return endpoints.Denied, entity.ListBlockReason().String()
+			return endpoints.Denied, entity.ListBlockReason()
 		}
 	}
 
-	return endpoints.NoMatch, ""
+	return endpoints.NoMatch, nil
 }
 
 // AddEndpoint adds an endpoint to the local endpoint list, saves the local profile and reloads the configuration.