diff --git a/Makefile.am b/Makefile.am
index 003ec9bfb7..f6699252d1 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -80,6 +80,8 @@ networkdir=$(rootprefix)/lib/systemd/network
 pkgincludedir=$(includedir)/systemd
 systemgeneratordir=$(rootlibexecdir)/system-generators
 usergeneratordir=$(prefix)/lib/systemd/user-generators
+systemenvgeneratordir=$(prefix)/lib/systemd/system-environment-generators
+userenvgeneratordir=$(prefix)/lib/systemd/user-environment-generators
 systemshutdowndir=$(rootlibexecdir)/system-shutdown
 systemsleepdir=$(rootlibexecdir)/system-sleep
 systemunitdir=$(rootprefix)/lib/systemd/system
@@ -205,6 +207,8 @@ AM_CPPFLAGS = \
 	-DSYSTEMD_CRYPTSETUP_PATH=\"$(rootlibexecdir)/systemd-cryptsetup\" \
 	-DSYSTEM_GENERATOR_PATH=\"$(systemgeneratordir)\" \
 	-DUSER_GENERATOR_PATH=\"$(usergeneratordir)\" \
+	-DSYSTEM_ENV_GENERATOR_PATH=\"$(systemenvgeneratordir)\" \
+	-DUSER_ENV_GENERATOR_PATH=\"$(userenvgeneratordir)\" \
 	-DSYSTEM_SHUTDOWN_PATH=\"$(systemshutdowndir)\" \
 	-DSYSTEM_SLEEP_PATH=\"$(systemsleepdir)\" \
 	-DSYSTEMD_KBD_MODEL_MAP=\"$(pkgdatadir)/kbd-model-map\" \
@@ -6210,6 +6214,8 @@ substitutions = \
        '|sysctldir=$(sysctldir)|' \
        '|systemgeneratordir=$(systemgeneratordir)|' \
        '|usergeneratordir=$(usergeneratordir)|' \
+       '|systemenvgeneratordir=$(systemenvgeneratordir)|' \
+       '|userenvgeneratordir=$(userenvgeneratordir)|' \
        '|CERTIFICATEROOT=$(CERTIFICATEROOT)|' \
        '|PACKAGE_VERSION=$(PACKAGE_VERSION)|' \
        '|PACKAGE_NAME=$(PACKAGE_NAME)|' \
diff --git a/src/core/macros.systemd.in b/src/core/macros.systemd.in
index 8d7ce1c238..a2a7edd1ee 100644
--- a/src/core/macros.systemd.in
+++ b/src/core/macros.systemd.in
@@ -31,6 +31,8 @@
 %_binfmtdir @binfmtdir@
 %_systemdgeneratordir @systemgeneratordir@
 %_systemdusergeneratordir @usergeneratordir@
+%_systemd_system_env_generator_dir @systemenvgeneratordir@
+%_systemd_user_env_generator_dir @userenvgeneratordir@
 
 %systemd_requires \
 Requires(post): systemd \
diff --git a/src/core/manager.c b/src/core/manager.c
index 6bbda1af0d..aefe4ca780 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -103,6 +103,7 @@ static int manager_dispatch_idle_pipe_fd(sd_event_source *source, int fd, uint32
 static int manager_dispatch_user_lookup_fd(sd_event_source *source, int fd, uint32_t revents, void *userdata);
 static int manager_dispatch_jobs_in_progress(sd_event_source *source, usec_t usec, void *userdata);
 static int manager_dispatch_run_queue(sd_event_source *source, void *userdata);
+static int manager_run_environment_generators(Manager *m);
 static int manager_run_generators(Manager *m);
 
 static void manager_watch_jobs_in_progress(Manager *m) {
@@ -1262,6 +1263,10 @@ int manager_startup(Manager *m, FILE *serialization, FDSet *fds) {
         if (r < 0)
                 return r;
 
+        r = manager_run_environment_generators(m);
+        if (r < 0)
+                return r;
+
         /* Make sure the transient directory always exists, so that it remains in the search path */
         if (!m->test_run) {
                 r = mkdir_p_label(m->lookup_paths.transient, 0755);
@@ -2795,6 +2800,10 @@ int manager_reload(Manager *m) {
         if (q < 0 && r >= 0)
                 r = q;
 
+        q = manager_run_environment_generators(m);
+        if (q < 0 && r >= 0)
+                r = q;
+
         /* Find new unit paths */
         q = manager_run_generators(m);
         if (q < 0 && r >= 0)
@@ -2986,10 +2995,56 @@ void manager_check_finished(Manager *m) {
         manager_invalidate_startup_units(m);
 }
 
+static bool generator_path_any(const char* const* paths) {
+        char **path;
+        bool found = false;
+
+        /* Optimize by skipping the whole process by not creating output directories
+         * if no generators are found. */
+        STRV_FOREACH(path, (char**) paths)
+                if (access(*path, F_OK) == 0)
+                        found = true;
+                else if (errno != ENOENT)
+                        log_warning_errno(errno, "Failed to open generator directory %s: %m", *path);
+
+        return found;
+}
+
+static const char* system_env_generator_binary_paths[] = {
+        "/run/systemd/system-environment-generators",
+        "/etc/systemd/system-environment-generators",
+        "/usr/local/lib/systemd/system-environment-generators",
+        SYSTEM_ENV_GENERATOR_PATH,
+        NULL
+};
+
+static const char* user_env_generator_binary_paths[] = {
+        "/run/systemd/user-environment-generators",
+        "/etc/systemd/user-environment-generators",
+        "/usr/local/lib/systemd/user-environment-generators",
+        USER_ENV_GENERATOR_PATH,
+        NULL
+};
+
+static int manager_run_environment_generators(Manager *m) {
+        char **tmp = NULL; /* this is only used in the forked process, no cleanup here */
+        const char **paths;
+        void* args[] = {&tmp, &tmp, &m->environment};
+
+        if (m->test_run)
+                return 0;
+
+        paths = MANAGER_IS_SYSTEM(m) ? system_env_generator_binary_paths : user_env_generator_binary_paths;
+
+        if (!generator_path_any(paths))
+                return 0;
+
+        return execute_directories(paths, DEFAULT_TIMEOUT_USEC, gather_environment, args, NULL);
+}
+
 static int manager_run_generators(Manager *m) {
         _cleanup_strv_free_ char **paths = NULL;
         const char *argv[5];
-        char **path;
         int r;
 
         assert(m);
@@ -3001,18 +3056,9 @@ static int manager_run_generators(Manager *m) {
         if (!paths)
                 return log_oom();
 
-        /* Optimize by skipping the whole process by not creating output directories
-         * if no generators are found. */
-        STRV_FOREACH(path, paths) {
-                if (access(*path, F_OK) >= 0)
-                        goto found;
-                if (errno != ENOENT)
-                        log_warning_errno(errno, "Failed to open generator directory %s: %m", *path);
-        }
+        if (!generator_path_any((const char* const*) paths))
+                return 0;
 
-        return 0;
-
- found:
         r = lookup_paths_mkdir_generator(&m->lookup_paths);
         if (r < 0)
                 goto finish;