diff --git a/src/fgai/dashboard.py b/src/fgai/dashboard.py
index ef64cc5..a46d7be 100644
--- a/src/fgai/dashboard.py
+++ b/src/fgai/dashboard.py
@@ -195,7 +195,7 @@ function profileDiscoveryDetails(row) {
   const advisor = row.profile_advisor || {};
   const fieldRoles = Object.entries(advisor.field_roles || {}).slice(0,12).map(([field, role]) => `${field}: ${role}`).join(', ');
   const correlationRoles = Object.entries(advisor.correlation_roles || {}).slice(0,8).map(([role, fields]) => `${role}: ${(fields || []).join(', ')}`).join('; ');
-  return `<details data-detail-id="${esc(detailId)}"><summary>${esc(d.field_count)} fields analyzed</summary><p><b>Selected</b><br>Entity: ${esc((selected.entity || []).join(', ') || '-')}<br>Time: ${esc((selected.time || []).join(', ') || '-')}<br>Categorical: ${esc((selected.categorical || []).join(', ') || '-')}<br>Numeric: ${esc((selected.numeric || []).join(', ') || '-')}</p><p><b>Shared across streams</b><br>${esc(shared || '-')}</p><p><b>Advisor roles</b><br>${esc(fieldRoles || '-')}<br>${esc(correlationRoles || '')}</p><p><b>Top fields</b><br>${esc(top || '-')}</p><p><b>Rejected</b><br>${esc(rejected || '-')}</p><p>${esc(reasons || '')}</p></details>`;
+  return `<details data-detail-id="${esc(detailId)}"><summary>${esc(d.field_count)} fields analyzed</summary><p><b>Selected</b><br>Entity: ${esc((selected.entity || []).join(', ') || '-')}<br>Time: ${esc((selected.time || []).join(', ') || '-')}<br>Categorical: ${esc((selected.categorical || []).join(', ') || '-')}<br>Numeric: ${esc((selected.numeric || []).join(', ') || '-')}<br>Relationships: ${esc((selected.relationships || []).join(', ') || '-')}</p><p><b>Shared across streams</b><br>${esc(shared || '-')}</p><p><b>Advisor roles</b><br>${esc(fieldRoles || '-')}<br>${esc(correlationRoles || '')}</p><p><b>Top fields</b><br>${esc(top || '-')}</p><p><b>Rejected</b><br>${esc(rejected || '-')}</p><p>${esc(reasons || '')}</p></details>`;
 }
 function sharedFieldLabel(item) {
   const aliases = (item.aliases || []).filter(alias => alias !== item.field).slice(0,4);
@@ -614,6 +614,16 @@ function renderStreamPicker(errorText='') {
 }
 function mergeProfile(existing, recommended) {
   const mergeList = (left, right) => [...new Set([...(left || []), ...(right || [])].filter(Boolean))];
+  const mergeRelationships = (left, right) => {
+    const rows = [...(left || []), ...(right || [])].filter(item => item && item.left && item.right);
+    const seen = new Set();
+    return rows.filter(item => {
+      const key = `${String(item.left).toLowerCase()}->${String(item.right).toLowerCase()}`;
+      if (seen.has(key)) return false;
+      seen.add(key);
+      return true;
+    });
+  };
   const detectors = {...(recommended.detectors || {}), ...(existing.detectors || {})};
   return {
     ...recommended,
@@ -626,7 +636,7 @@ function mergeProfile(existing, recommended) {
     numeric_fields: mergeList(existing.numeric_fields, recommended.numeric_fields),
     detectors,
     field_weights: {...(recommended.field_weights || {}), ...(existing.field_weights || {})},
-    relationship_fields: existing.relationship_fields || recommended.relationship_fields || []
+    relationship_fields: mergeRelationships(existing.relationship_fields, recommended.relationship_fields)
   };
 }
 async function applySuggestedProfile(streamId) {
diff --git a/src/fgai/profile_suggestions.py b/src/fgai/profile_suggestions.py
index c9a7106..40b8aff 100644
--- a/src/fgai/profile_suggestions.py
+++ b/src/fgai/profile_suggestions.py
@@ -421,6 +421,95 @@ def _generic_numeric_fields(coverage: Counter[str], numeric_counts: Counter[str]
     return output
 
 
+def _relationship_name(left: str, right: str) -> str:
+    return f"{left} to {right}"
+
+
+def _field_matches(field: str, groups: set[str], tokens: set[str]) -> bool:
+    lower = field.lower()
+    semantic = set(_semantic_field_groups(lower))
+    return bool(semantic & groups) or any(token in lower for token in tokens)
+
+
+def _relationship_candidates(
+    coverage: Counter[str],
+    unique_values: dict[str, set[str]],
+    total: int,
+    entity_fields: list[str],
+    categorical_fields: list[str],
+    numeric_fields: list[str],
+    *,
+    limit: int = 6,
+) -> list[dict[str, str]]:
+    def usable(field: str) -> bool:
+        return (
+            bool(field)
+            and field in coverage
+            and field not in IGNORED_DISCOVERY_FIELDS
+            and coverage[field] / max(1, total) >= 0.02
+            and len(unique_values[field]) > 1
+        )
+
+    candidates: list[tuple[str, str]] = []
+    entities = [field for field in entity_fields if usable(field)]
+    categorical = [field for field in categorical_fields if usable(field)]
+    numeric = [field for field in numeric_fields if usable(field)]
+
+    identity_fields = [
+        field for field in entities
+        if _field_matches(field, {"username", "*_user"}, {"user", "account", "actor", "principal", "login", "identity"})
+    ]
+    source_fields = [
+        field for field in entities
+        if _field_matches(field, {"srcip", "*_ip"}, {"src", "source", "client", "remote", "ipaddress", "clientip"})
+    ]
+    host_fields = [
+        field for field in entities
+        if _field_matches(field, {"*_host"}, {"host", "hostname", "computer", "workstation", "device"})
+    ]
+    destination_fields = [
+        field for field in [*entities, *categorical]
+        if _field_matches(field, {"dstip", "*_ip"}, {"dst", "dest", "destination", "server"})
+    ]
+    destination_fields.extend(field for field in categorical if field.lower() in {"dstport", "destination_port", "dest_port", "service", "application", "app", "url", "query_domain", "dns_query"})
+
+    for left in identity_fields:
+        for right in [*source_fields, *host_fields]:
+            if left != right:
+                candidates.append((left, right))
+    for left in source_fields:
+        for right in destination_fields:
+            if left != right:
+                candidates.append((left, right))
+    for left in host_fields:
+        for right in [field for field in categorical if any(token in field.lower() for token in ("process", "service", "app", "action", "status", "event"))]:
+            if left != right:
+                candidates.append((left, right))
+
+    behavior_fields = [
+        field for field in [*categorical, *numeric]
+        if field not in entities
+        and not _looks_like_time_field(field)
+        and not any(token in field.lower() for token in ("gl2_", "message_id", "sort_field", "accounted_message_size", "processing_timestamp"))
+    ]
+    for left in entities:
+        for right in behavior_fields[:4]:
+            if left != right:
+                candidates.append((left, right))
+
+    output = []
+    seen = set()
+    for left, right in candidates:
+        key = (left.lower(), right.lower())
+        if key in seen:
+            continue
+        seen.add(key)
+        output.append({"left": left, "right": right, "name": _relationship_name(left, right)})
+        if len(output) >= limit:
+            break
+    return output
+
+
 def _shared_profile_fields(
     coverage: Counter[str],
     unique_values: dict[str, set[str]],
@@ -723,11 +812,12 @@ def suggest_stream_profiles(events: list[LogEvent], *, existing_profiles: dict[s
             detectors.setdefault("auth_failure", {"enabled": True, "minimum": 5, "z_threshold": 3.0})
         if not detectors:
             detectors = {"deny_action": {"enabled": True, "minimum": 10, "z_threshold": 3.0}}
+        relationship_fields = _relationship_candidates(coverage, unique_values, total, entity_fields, categorical, numeric)
         high_coverage = [
             {"field": field, "coverage": round(count / max(1, total), 2), "unique_values": len(unique_values[field])}
             for field, count in coverage.most_common(12)
         ]
-        selected_fields = {timestamp, *entity_fields, *categorical, *numeric}
+        selected_fields = {timestamp, *entity_fields, *categorical, *numeric, *(item["left"] for item in relationship_fields), *(item["right"] for item in relationship_fields)}
         discovery = {
             "log_type": log_type,
             "field_count": len([field for field in coverage if field not in IGNORED_DISCOVERY_FIELDS]),
@@ -736,13 +826,14 @@ def suggest_stream_profiles(events: list[LogEvent], *, existing_profiles: dict[s
                 "time": [timestamp] if timestamp else [],
                 "categorical": categorical,
                 "numeric": numeric,
+                "relationships": [f"{item['left']}->{item['right']}" for item in relationship_fields],
             },
             "top_fields": _field_stats(coverage, unique_values, numeric_counts, total)[:16],
             "shared_fields": shared_stats,
             "rejected_fields": _rejected_fields(coverage, unique_values, numeric_counts, total, selected_fields),
             "reasons": [
                 f"detected {log_type} log pattern",
-                f"selected {len(entity_fields)} entity field(s), {len(categorical)} categorical field(s), and {len(numeric)} numeric field(s)",
+                f"selected {len(entity_fields)} entity field(s), {len(categorical)} categorical field(s), {len(numeric)} numeric field(s), and {len(relationship_fields)} relationship(s)",
                 f"found {len(shared_stats)} field(s) that also appear in other enabled streams",
                 "ignored raw/internal, constant, sparse, and very high-cardinality fields",
             ],
@@ -760,6 +851,7 @@ def suggest_stream_profiles(events: list[LogEvent], *, existing_profiles: dict[s
             "timestamp_field": timestamp,
             "categorical_fields": categorical,
             "numeric_fields": numeric,
+            "relationship_fields": relationship_fields,
             "detectors": detectors,
             "common_fields": high_coverage,
             "shared_fields": shared_stats,
@@ -775,7 +867,7 @@ def suggest_stream_profiles(events: list[LogEvent], *, existing_profiles: dict[s
                 "numeric_fields": numeric,
                 "detectors": detectors,
                 "field_weights": {},
-                "relationship_fields": [],
+                "relationship_fields": relationship_fields,
             },
             "reason": "selected common entity, time, categorical, and numeric fields from observed events; non-priority fields are included when coverage and cardinality look useful",
         })
diff --git a/tests/test_profile_suggestions.py b/tests/test_profile_suggestions.py
index 0d3a6e4..eec1166 100644
--- a/tests/test_profile_suggestions.py
+++ b/tests/test_profile_suggestions.py
@@ -221,6 +221,34 @@ class ProfileSuggestionTests(unittest.TestCase):
             self.assertIn("*_status", shared)
             self.assertIn("*_name", shared)
 
+    def test_heuristic_profile_recommends_behavior_relationships(self):
+        events = [
+            parse_log_line(
+                f"fgai_stream_id=windows fgai_stream=Windows username=user{index % 3} srcip=10.0.0.{index % 5} hostname=host{index % 4} action=success eventid=4624"
+            )
+            for index in range(1, 40)
+        ]
+
+        suggestion = suggest_stream_profiles(events)[0]
+        relationships = {(item["left"], item["right"]) for item in suggestion["relationship_fields"]}
+
+        self.assertIn(("username", "srcip"), relationships)
+        self.assertIn("username->srcip", suggestion["discovery"]["selected_fields"]["relationships"])
+        self.assertEqual(suggestion["profile"]["relationship_fields"], suggestion["relationship_fields"])
+
+    def test_heuristic_profile_recommends_generic_entity_behavior_relationships(self):
+        events = [
+            parse_log_line(
+                f"fgai_stream_id=app fgai_stream=App entry_context_clientipaddress=10.0.0.{index % 5} entry_context_type={'login' if index % 2 else 'update'} houston_category=cat{index % 3}"
+            )
+            for index in range(1, 40)
+        ]
+
+        suggestion = suggest_stream_profiles(events)[0]
+        relationships = {(item["left"], item["right"]) for item in suggestion["relationship_fields"]}
+
+        self.assertIn(("entry_context_clientipaddress", "entry_context_type"), relationships)
+
     def test_applies_valid_llm_advice_and_rejects_unknown_fields(self):
         suggestion = suggest_stream_profiles([
             parse_log_line("fgai_stream_id=windows fgai_stream=Windows username=alice hostname=host01 eventid=4625 action=failure")