diff --git a/doc/src/sgml/event-trigger.sgml b/doc/src/sgml/event-trigger.sgml
index f1235a2c9f..3f9110f4e9 100644
--- a/doc/src/sgml/event-trigger.sgml
+++ b/doc/src/sgml/event-trigger.sgml
@@ -28,6 +28,7 @@
      An event trigger fires whenever the event with which it is associated
      occurs in the database in which it is defined. Currently, the only
      supported events are
+     <literal>login</literal>,
      <literal>ddl_command_start</literal>,
      <literal>ddl_command_end</literal>,
      <literal>table_rewrite</literal>
@@ -35,6 +36,18 @@
      Support for additional events may be added in future releases.
    </para>
 
+   <para>
+     The <literal>login</literal> event occurs when an authenticated user logs
+     in to the system. Any bugs in a trigger procedure for this event may
+     prevent successful login to the system. Such bugs may be fixed by
+     restarting the system in single-user mode (as event triggers are
+     disabled in this mode). See the <xref linkend="app-postgres"/> reference
+     page for details about using single-user mode.
+     The <literal>login</literal> event will also fire on standby servers.
+     To prevent servers from becoming inaccessible, such triggers must avoid
+     writing anything to the database when running on a standby.
+   </para>
+
    <para>
      The <literal>ddl_command_start</literal> event occurs just before the
      execution of a <literal>CREATE</literal>, <literal>ALTER</literal>, <literal>DROP</literal>,
@@ -1299,4 +1312,79 @@ CREATE EVENT TRIGGER no_rewrite_allowed
 </programlisting>
    </para>
  </sect1>
+
+  <sect1 id="event-trigger-database-login-example">
+    <title>A Database Login Event Trigger Example</title>
+
+    <para>
+      The event trigger on the <literal>login</literal> event can be
+      useful for logging user logins, for verifying the connection and
+      assigning roles according to current circumstances, or for session
+      data initialization. It is very important that any event trigger using
+      the <literal>login</literal> event checks whether or not the database is
+      in recovery before performing any writes. Writing to a standby server
+      will make it inaccessible.
+    </para>
+
+    <para>
+      The following example demonstrates these options.
+<programlisting>
+-- create test tables and roles
+CREATE TABLE user_login_log (
+  "user" text,
+  "session_start" timestamp with time zone
+);
+CREATE ROLE day_worker;
+CREATE ROLE night_worker;
+
+-- the example trigger function
+CREATE OR REPLACE FUNCTION init_session()
+  RETURNS event_trigger SECURITY DEFINER
+  LANGUAGE plpgsql AS
+$$
+DECLARE
+  hour integer = EXTRACT('hour' FROM current_time at time zone 'utc');
+  rec boolean;
+BEGIN
+-- 1. Forbid logging in between 2AM and 4AM.
+IF hour BETWEEN 2 AND 4 THEN
+  RAISE EXCEPTION 'Login forbidden';
+END IF;
+
+-- The checks below cannot be performed on standby servers so
+-- ensure the database is not in recovery before we perform any
+-- operations.
+SELECT pg_is_in_recovery() INTO rec;
+IF rec THEN
+  RETURN;
+END IF;
+
+-- 2. Assign some roles. At daytime, grant the day_worker role, else the
+-- night_worker role.
+IF hour BETWEEN 8 AND 20 THEN
+  EXECUTE 'REVOKE night_worker FROM ' || quote_ident(session_user);
+  EXECUTE 'GRANT day_worker TO ' || quote_ident(session_user);
+ELSE
+  EXECUTE 'REVOKE day_worker FROM ' || quote_ident(session_user);
+  EXECUTE 'GRANT night_worker TO ' || quote_ident(session_user);
+END IF;
+
+-- 3. Initialize user session data
+CREATE TEMP TABLE session_storage (x float, y integer);
+ALTER TABLE session_storage OWNER TO session_user;
+
+-- 4. Log the connection time
+INSERT INTO public.user_login_log VALUES (session_user, current_timestamp);
+
+END;
+$$;
+
+-- trigger definition
+CREATE EVENT TRIGGER init_session
+  ON login
+  EXECUTE FUNCTION init_session();
+ALTER EVENT TRIGGER init_session ENABLE ALWAYS;
+</programlisting>
+    </para>
+  </sect1>
 </chapter>
diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
index a3bdc5db07..6971a5474a 100644
--- a/src/backend/commands/event_trigger.c
+++ b/src/backend/commands/event_trigger.c
@@ -20,6 +20,7 @@
 #include "catalog/dependency.h"
 #include "catalog/indexing.h"
 #include "catalog/objectaccess.h"
+#include "catalog/pg_database.h"
 #include "catalog/pg_event_trigger.h"
 #include "catalog/pg_namespace.h"
 #include "catalog/pg_opclass.h"
@@ -37,15 +38,18 @@
 #include "miscadmin.h"
 #include "parser/parse_func.h"
 #include "pgstat.h"
+#include "storage/lmgr.h"
 #include "tcop/deparse_utility.h"
 #include "tcop/utility.h"
 #include "utils/acl.h"
 #include "utils/builtins.h"
 #include "utils/evtcache.h"
 #include "utils/fmgroids.h"
+#include "utils/inval.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"
+#include "utils/snapmgr.h"
 #include "utils/syscache.h"
 
 typedef struct EventTriggerQueryState
@@ -130,6 +134,7 @@ CreateEventTrigger(CreateEventTrigStmt *stmt)
 	if (strcmp(stmt->eventname, "ddl_command_start") != 0 &&
 		strcmp(stmt->eventname, "ddl_command_end") != 0 &&
 		strcmp(stmt->eventname, "sql_drop") != 0 &&
+		strcmp(stmt->eventname, "login") != 0 &&
 		strcmp(stmt->eventname, "table_rewrite") != 0)
 		ereport(ERROR,
 				(errcode(ERRCODE_SYNTAX_ERROR),
@@ -579,10 +584,15 @@ EventTriggerCommonSetup(Node *parsetree,
 	{
 		CommandTag	dbgtag;
 
-		dbgtag = CreateCommandTag(parsetree);
+		if (event == EVT_Login)
+			dbgtag = CMDTAG_LOGIN;
+		else
+			dbgtag = CreateCommandTag(parsetree);
+
 		if (event == EVT_DDLCommandStart ||
 			event == EVT_DDLCommandEnd ||
-			event == EVT_SQLDrop)
+			event == EVT_SQLDrop ||
+			event == EVT_Login)
 		{
 			if (!command_tag_event_trigger_ok(dbgtag))
 				elog(ERROR, "unexpected command tag \"%s\"", GetCommandTagName(dbgtag));
@@ -601,7 +611,10 @@ EventTriggerCommonSetup(Node *parsetree,
 		return NIL;
 
 	/* Get the command tag. */
-	tag = CreateCommandTag(parsetree);
+	if (event == EVT_Login)
+		tag = CMDTAG_LOGIN;
+	else
+		tag = CreateCommandTag(parsetree);
 
 	/*
 	 * Filter list of event triggers by command tag, and copy them into our
@@ -799,6 +812,46 @@ EventTriggerSQLDrop(Node *parsetree)
 	list_free(runlist);
 }
 
+/*
+ * Fire login event triggers if any are present.
+ */
+void
+EventTriggerOnLogin(void)
+{
+	List	   *runlist;
+	EventTriggerData trigdata;
+
+	/*
+	 * See EventTriggerDDLCommandStart for a discussion about why event
+	 * triggers are disabled in single user mode.
+	 */
+	if (!IsUnderPostmaster || !OidIsValid(MyDatabaseId))
+		return;
+
+	StartTransactionCommand();
+
+	/* Find login triggers and run what was found */
+	runlist = EventTriggerCommonSetup(NULL,
+										EVT_Login, "login",
+										&trigdata);
+
+	if (runlist != NIL)
+	{
+		/* Event trigger execution may require an active snapshot. */
+		PushActiveSnapshot(GetTransactionSnapshot());
+
+		/* Run the triggers. */
+		EventTriggerInvoke(runlist, &trigdata);
+
+		/* Cleanup. */
+		list_free(runlist);
+
+		PopActiveSnapshot();
+	}
+
+	CommitTransactionCommand();
+}
+
 
 /*
  * Fire table_rewrite triggers.
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 01d264b5ab..6235269b4b 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -33,6 +33,7 @@
 #include "access/xact.h"
 #include "catalog/pg_type.h"
 #include "commands/async.h"
+#include "commands/event_trigger.h"
 #include "commands/prepare.h"
 #include "common/pg_prng.h"
 #include "jit/jit.h"
@@ -4217,6 +4218,9 @@ PostgresMain(const char *dbname, const char *username)
 	initStringInfo(&row_description_buf);
 	MemoryContextSwitchTo(TopMemoryContext);
 
+	/* Fire any defined login event triggers, if appropriate */
+	EventTriggerOnLogin();
+
 	/*
 	 * POSTGRES main processing loop begins here
 	 *
diff --git a/src/backend/utils/cache/evtcache.c b/src/backend/utils/cache/evtcache.c
index f7f7165f7f..3e9388e956 100644
--- a/src/backend/utils/cache/evtcache.c
+++ b/src/backend/utils/cache/evtcache.c
@@ -167,6 +167,8 @@ BuildEventTriggerCache(void)
 			event = EVT_SQLDrop;
 		else if (strcmp(evtevent, "table_rewrite") == 0)
 			event = EVT_TableRewrite;
+		else if (strcmp(evtevent, "login") == 0)
+			event = EVT_Login;
 		else
 			continue;
 
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 2a3921937c..a9f16b5e3a 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3453,8 +3453,8 @@ psql_completion(const char *text, int start, int end)
 		COMPLETE_WITH("ON");
 	/* Complete CREATE EVENT TRIGGER <name> ON with event_type */
 	else if (Matches("CREATE", "EVENT", "TRIGGER", MatchAny, "ON"))
-		COMPLETE_WITH("ddl_command_start", "ddl_command_end", "sql_drop",
-					  "table_rewrite");
+		COMPLETE_WITH("ddl_command_start", "ddl_command_end", "login",
+					  "sql_drop", "table_rewrite");
 
 	/*
 	 * Complete CREATE EVENT TRIGGER <name> ON <event_type>.  EXECUTE FUNCTION
diff --git a/src/include/commands/event_trigger.h b/src/include/commands/event_trigger.h
index 10091c3aaf..c9efee59bf 100644
--- a/src/include/commands/event_trigger.h
+++ b/src/include/commands/event_trigger.h
@@ -54,6 +54,7 @@ extern void EventTriggerDDLCommandStart(Node *parsetree);
 extern void EventTriggerDDLCommandEnd(Node *parsetree);
 extern void EventTriggerSQLDrop(Node *parsetree);
 extern void EventTriggerTableRewrite(Node *parsetree, Oid tableOid, int reason);
+extern void EventTriggerOnLogin(void);
 
 extern bool EventTriggerBeginCompleteQuery(void);
 extern void EventTriggerEndCompleteQuery(void);
diff --git a/src/include/tcop/cmdtaglist.h b/src/include/tcop/cmdtaglist.h
index 9e94f44c5f..b900227e0c 100644
--- a/src/include/tcop/cmdtaglist.h
+++ b/src/include/tcop/cmdtaglist.h
@@ -186,6 +186,7 @@ PG_CMDTAG(CMDTAG_INSERT, "INSERT", false, false, true)
 PG_CMDTAG(CMDTAG_LISTEN, "LISTEN", false, false, false)
 PG_CMDTAG(CMDTAG_LOAD, "LOAD", false, false, false)
 PG_CMDTAG(CMDTAG_LOCK_TABLE, "LOCK TABLE", false, false, false)
+PG_CMDTAG(CMDTAG_LOGIN, "LOGIN", true, false, false)
 PG_CMDTAG(CMDTAG_MERGE, "MERGE", false, false, true)
 PG_CMDTAG(CMDTAG_MOVE, "MOVE", false, false, true)
 PG_CMDTAG(CMDTAG_NOTIFY, "NOTIFY", false, false, false)
diff --git a/src/include/utils/evtcache.h b/src/include/utils/evtcache.h
index ddb67a68fa..a66344aacb 100644
--- a/src/include/utils/evtcache.h
+++ b/src/include/utils/evtcache.h
@@ -22,7 +22,8 @@ typedef enum
 	EVT_DDLCommandStart,
 	EVT_DDLCommandEnd,
 	EVT_SQLDrop,
-	EVT_TableRewrite
+	EVT_TableRewrite,
+	EVT_Login,
 } EventTriggerEvent;
 
 typedef struct
diff --git a/src/test/recovery/t/001_stream_rep.pl b/src/test/recovery/t/001_stream_rep.pl
index 986147b730..8ad50762c4 100644
--- a/src/test/recovery/t/001_stream_rep.pl
+++ b/src/test/recovery/t/001_stream_rep.pl
@@ -46,6 +46,24 @@ $node_standby_2->start;
 $node_primary->safe_psql('postgres',
 	"CREATE TABLE tab_int AS SELECT generate_series(1,1002) AS a");
 
+$node_primary->safe_psql('postgres', q{
+CREATE TABLE user_logins(id serial, who text);
+
+CREATE FUNCTION on_login_proc() RETURNS EVENT_TRIGGER AS $$
+BEGIN
+  IF NOT pg_is_in_recovery() THEN
+    INSERT INTO user_logins (who) VALUES (session_user);
+  END IF;
+  IF session_user = 'regress_hacker' THEN
+    RAISE EXCEPTION 'You are not welcome!';
+  END IF;
+END;
+$$ LANGUAGE plpgsql SECURITY DEFINER;
+
+CREATE EVENT TRIGGER on_login_trigger ON login EXECUTE FUNCTION on_login_proc();
+ALTER EVENT TRIGGER on_login_trigger ENABLE ALWAYS;
+});
+
 # Wait for standbys to catch up
 my $primary_lsn = $node_primary->lsn('write');
 $node_primary->wait_for_catchup($node_standby_1, 'replay', $primary_lsn);
@@ -388,6 +406,11 @@ sub replay_check
 
 replay_check();
 
+my $evttrig = $node_standby_1->safe_psql('postgres', "SELECT evtname FROM pg_event_trigger WHERE evtevent = 'login'");
+is($evttrig, 'on_login_trigger', 'Name of login trigger');
+$evttrig = $node_standby_2->safe_psql('postgres', "SELECT evtname FROM pg_event_trigger WHERE evtevent = 'login'");
+is($evttrig, 'on_login_trigger', 'Name of login trigger');
+
 note "enabling hot_standby_feedback";
 
 # Enable hs_feedback. The slot should gain an xmin. We set the status interval
diff --git a/src/test/regress/expected/event_trigger.out b/src/test/regress/expected/event_trigger.out
index 5a10958df5..433f5f6e95 100644
--- a/src/test/regress/expected/event_trigger.out
+++ b/src/test/regress/expected/event_trigger.out
@@ -614,3 +614,34 @@ SELECT
 DROP EVENT TRIGGER start_rls_command;
 DROP EVENT TRIGGER end_rls_command;
 DROP EVENT TRIGGER sql_drop_command;
+-- Login event triggers
+CREATE TABLE user_logins(id serial, who text);
+GRANT SELECT ON user_logins TO public;
+CREATE FUNCTION on_login_proc() RETURNS event_trigger AS $$
+BEGIN
+  INSERT INTO user_logins (who) VALUES (SESSION_USER);
+  RAISE NOTICE 'You are welcome!';
+END;
+$$ LANGUAGE plpgsql;
+CREATE EVENT TRIGGER on_login_trigger ON login EXECUTE PROCEDURE on_login_proc();
+ALTER EVENT TRIGGER on_login_trigger ENABLE ALWAYS;
+\c
+NOTICE:  You are welcome!
+SELECT COUNT(*) FROM user_logins;
+ count 
+-------
+     1
+(1 row)
+
+\c
+NOTICE:  You are welcome!
+SELECT COUNT(*) FROM user_logins;
+ count 
+-------
+     2
+(1 row)
+
+-- Cleanup
+DROP TABLE user_logins;
+DROP EVENT TRIGGER on_login_trigger;
+DROP FUNCTION on_login_proc();
diff --git a/src/test/regress/sql/event_trigger.sql b/src/test/regress/sql/event_trigger.sql
index 1aeaddbe71..420224f3ba 100644
--- a/src/test/regress/sql/event_trigger.sql
+++ b/src/test/regress/sql/event_trigger.sql
@@ -471,3 +471,24 @@ SELECT
 DROP EVENT TRIGGER start_rls_command;
 DROP EVENT TRIGGER end_rls_command;
 DROP EVENT TRIGGER sql_drop_command;
+
+-- Login event triggers
+CREATE TABLE user_logins(id serial, who text);
+GRANT SELECT ON user_logins TO public;
+CREATE FUNCTION on_login_proc() RETURNS event_trigger AS $$
+BEGIN
+  INSERT INTO user_logins (who) VALUES (SESSION_USER);
+  RAISE NOTICE 'You are welcome!';
+END;
+$$ LANGUAGE plpgsql;
+CREATE EVENT TRIGGER on_login_trigger ON login EXECUTE PROCEDURE on_login_proc();
+ALTER EVENT TRIGGER on_login_trigger ENABLE ALWAYS;
+\c
+SELECT COUNT(*) FROM user_logins;
+\c
+SELECT COUNT(*) FROM user_logins;
+
+-- Cleanup
+DROP TABLE user_logins;
+DROP EVENT TRIGGER on_login_trigger;
+DROP FUNCTION on_login_proc();