diff --git a/doc/manuals/chapters/remsim-client.adoc b/doc/manuals/chapters/remsim-client.adoc
index 8f90a1a..7416b05 100644
--- a/doc/manuals/chapters/remsim-client.adoc
+++ b/doc/manuals/chapters/remsim-client.adoc
@@ -82,6 +82,10 @@
   Specify the initial ATR to be communicated to the modem/phone.  Can
   and will later be overridden by the ATR as specified by
   `osmo-remsim-bankd` once a card has been mapped to this client.
+*-e, --event-script COMMAND*::
+  Specify the shell command to be execute when the client wants to call its
+  helper script
+
 
 ==== Examples
 .remsim-server is on 10.2.3.4, sysmoQMOD on usb bus, all 4 modems:
@@ -97,3 +101,55 @@
 `osmo-remsim-client` currently logs to stdout only, and the logging
 verbosity is not yet configurable.  However, as the libosmocore logging
 framework is used, extending this is an easy modification.
+
+=== Helper Script
+
+`osmo-remsim-client` can call an external shell command / script / program at specific
+instances of time.  This serves two purposes:
+
+* To keep external system integration posted about the overall status of remsim-client,
+  such as whether or not it is connected to a server and/or bankd.
+* To request the external system to perform specific actions, such as triggering the reset
+  of the modem - in case the hardware doesn't allow the simtrace2 firmware to do that itself.
+
+==== Script Environment Variables
+
+The environment passed to the helper script contains a number of variables to provide inormation
+to the external script:
+
+.Environment Variables
+[options="header",cols="27%,18%,55%"]
+|===
+| Name | Example Value | Description
+| REMSIM_CLIENT_VERSION | 0.2.2.37-5406a | Compile version of the software
+| REMSIM_SERVER_ADDR | 1.2.3.4:1234 | Address and port of the remsim-server
+| REMSIM_SERVER_STATE | CONNECTED | FSM state of the connection to remsim-server
+| REMSIM_BANKD_ADDR | 1.2.3.4:1234 | Address and port of the remsim-bankd
+| REMSIM_BANKD_STATE | CONNECTED | FSM state of the connection to remsim-bankd
+| REMSIM_CLIENT_SLOT | 23:42 | Client ID and Client Slot Number
+| REMSIM_BANKD_SLOT | 55:33 | Bank ID and Bank Slot Number
+| REMSIM_USB_PATH | 2-1.1 | USB path of the USB device with simtrace2 cardem firmware
+| REMSIM_USB_INTERFACE | 1 | Interface number of the USB device with simtrace2 cardem firmware
+| REMSIM_SIM_VCC | 1 | Whether or not the modem currently applies SIM VCC (0/1)
+| REMSIM_SIM_RST | 1 | Whether or not the modem currently asserts SIM RST (0=inactive, 1=active)
+| REMSIM_CAUSE | request-card-insert | The cause why this script has been called
+|===
+
+==== REMSIM_CAUSE values
+
+The REMSIM_CAUSE environment variable (as well as the first argument) passed to the helper
+script indicated why the script has been called.
+
+[options="header",cols="25%,75%"]
+|===
+| Name | Description
+| event-modem-status | The SIM card interface status has changed (e.g. VCC/RST change)
+| event-bankd-connect | A logical RSPRO connection to a bankd has been established
+| event-server-connect | A logical RSPRO connection to a server has been established
+| event-config-bankd | The server has instructed the client of the bankd address
+| request-card-insert | The client asks the system to simulate SIM card insertion to the modem
+| request-card-remove | The client asks the system to simulate SIM card removal from the modem
+| request-sim-remote | The client asks the system to switch to remote SIM
+| request-sim-local | The client asks the system to switch to local SIM
+| request-modem-reset | The client asks the system to perform a modem reset
+|===
diff --git a/src/client/simtrace2-remsim_client.c b/src/client/simtrace2-remsim_client.c
index 846ce85..ce8ea1d 100644
--- a/src/client/simtrace2-remsim_client.c
+++ b/src/client/simtrace2-remsim_client.c
@@ -32,6 +32,7 @@
 #include <osmocom/core/utils.h>
 #include <osmocom/core/logging.h>
 #include <osmocom/core/application.h>
+#include <osmocom/core/exec.h>
 
 #include <osmocom/abis/ipa.h>
 #include <osmocom/gsm/protocol/ipaccess.h>
@@ -130,6 +131,77 @@
 	return 0;
 }
 
+/* build the (additional) environment for executing a script */
+static char **build_script_env(struct bankd_client *clnt, const char *cause)
+{
+	struct cardem_inst *ci = clnt->cardem;
+	char **env = talloc_zero_size(clnt, 256*sizeof(char *));
+	int i = 0;
+
+	if (!env)
+		return NULL;
+
+	env[i++] = talloc_asprintf(env, "REMSIM_CLIENT_VERSION=%s", VERSION);
+
+	env[i++] = talloc_asprintf(env, "REMSIM_SERVER_ADDR=%s:%u",
+				   clnt->srv_conn.server_host, clnt->srv_conn.server_port);
+	env[i++] = talloc_asprintf(env, "REMSIM_SERVER_STATE=%s",
+				   osmo_fsm_inst_state_name(clnt->srv_conn.fi));
+
+	env[i++] = talloc_asprintf(env, "REMSIM_BANKD_ADDR=%s:%u",
+				   clnt->bankd_conn.server_host, clnt->bankd_conn.server_port);
+	env[i++] = talloc_asprintf(env, "REMSIM_BANKD_STATE=%s",
+				   osmo_fsm_inst_state_name(clnt->bankd_conn.fi));
+
+
+	if (clnt->srv_conn.clslot) {
+		env[i++] = talloc_asprintf(env, "REMSIM_CLIENT_SLOT=%lu:%lu",
+					   g_client->srv_conn.clslot->clientId,
+					   g_client->srv_conn.clslot->slotNr);
+	}
+	env[i++] = talloc_asprintf(env, "REMSIM_BANKD_SLOT=%u:%u",
+				   clnt->bankd_slot.bank_id, clnt->bankd_slot.slot_nr);
+
+	env[i++] = talloc_asprintf(env, "REMSIM_USB_PATH=%s", ci->usb_path);
+	env[i++] = talloc_asprintf(env, "REMSIM_USB_INTERFACE=%u", clnt->cfg->usb.if_num);
+
+	/* TODO: SIM card state VCC/CLK/RST */
+	env[i++] = talloc_asprintf(env, "REMSIM_SIM_VCC=%u",
+				   !!(ci->last_status.flags & CEMU_STATUS_F_VCC_PRESENT));
+	env[i++] = talloc_asprintf(env, "REMSIM_SIM_RST=%u",
+				   !!(ci->last_status.flags & CEMU_STATUS_F_RESET_ACTIVE));
+
+	env[i++] = talloc_asprintf(env, "REMSIM_CAUSE=%s", cause);
+
+	/* terminate last entry */
+	env[i++] = NULL;
+	return env;
+}
+
+static int call_script(struct bankd_client *clnt, const char *cause)
+{
+	char **env, *cmd;
+	int rc;
+
+	if (!clnt->cfg->event_script)
+		return 0;
+
+	env = build_script_env(clnt, cause);
+	if (!env)
+		return -ENOMEM;
+
+	cmd = talloc_asprintf(env, "%s %s", clnt->cfg->event_script, cause);
+	if (!cmd) {
+		talloc_free(env);
+		return -ENOMEM;
+	}
+
+	rc = osmo_system_nowait(cmd, osmo_environment_whitelist, env);
+	talloc_free(env);
+
+	return rc;
+}
+
 /***********************************************************************
  * SIMTRACE core protocol
  ***********************************************************************/
@@ -548,6 +620,7 @@
 
 	if (ci->last_status.flags != status->flags) {
 		ci->last_status = *status;
+		call_script(g_client, "event-modem-status");
 	} else
 		ci->last_status = *status;
 
@@ -754,6 +827,7 @@
 		/* Store 'identity' of bankd to in peer_comp_id */
 		rspro_comp_id_retrieve(&bankdc->peer_comp_id, &pdu->msg.choice.connectClientRes.identity);
 		osmo_fsm_inst_dispatch(bankdc->fi, SRVC_E_CLIENT_CONN_RES, (void *) pdu);
+		call_script(g_client, "event-bankd-connect");
 		break;
 	case RsproPDUchoice_PR_tpduCardToModem: // APDU response from card received
 		bankd_handle_tpduCardToModem(g_client, pdu);
@@ -780,6 +854,7 @@
 		/* Store 'identity' of server in srvc->peer_comp_id */
 		rspro_comp_id_retrieve(&srvc->peer_comp_id, &pdu->msg.choice.connectClientRes.identity);
 		osmo_fsm_inst_dispatch(srvc->fi, SRVC_E_CLIENT_CONN_RES, (void *) pdu);
+		call_script(g_client, "event-server-connect");
 		break;
 	case RsproPDUchoice_PR_configClientIdReq:
 		/* store/set the clientID as instructed by the server */
@@ -804,6 +879,7 @@
 		/* send response to server */
 		resp = rspro_gen_ConfigClientBankRes(ResultCode_ok);
 		server_conn_send_rspro(srvc, resp);
+		call_script(g_client, "event-config-bankd");
 		break;
 	default:
 		LOGPFSML(srvc->fi, LOGL_ERROR, "Unknown/Unsupported RSPRO PDU type: %s\n",
@@ -847,6 +923,7 @@
 		"\t-A\t--usb-address\tADDRESS\n"
 		"\t-H\t--usb-path\tPATH\n"
 		"\t-a\t--atr\tATR\n"
+		"\t-e\t--event-script\tPATH\n"
 		"\n"
 		);
 }
@@ -898,6 +975,7 @@
 		{ "usb-address", 1, 0, 'A' },
 		{ "usb-path", 1, 0, 'H' },
 		{ "atr", 1, 0, 'a' },
+		{ "event-script", 1, 0, 'e' },
 		{ NULL, 0, 0, 0 }
 	};
 	int c, rc;
@@ -905,7 +983,7 @@
 	while (1) {
 		int option_index = 0;
 
-		c = getopt_long(argc, argv, "s:p:c:n:hvi:kV:P:C:I:S:A:H:a:", opts, &option_index);
+		c = getopt_long(argc, argv, "s:p:c:n:hvi:kV:P:C:I:S:A:H:a:e:", opts, &option_index);
 		if (c == -1)
 			break;
 		switch (c) {
@@ -964,6 +1042,9 @@
 			}
 			cfg->atr.len = rc;
 			break;
+		case 'e':
+			osmo_talloc_replace_string(cfg, &cfg->event_script, optarg);
+			break;
 		}
 	}
 
@@ -1062,9 +1143,11 @@
 
 	/* simulate card-insert to modem (owhw, not qmod) */
 	cardem_request_card_insert(ci, true);
+	call_script(g_client, "request-card-insert");
 
 	/* select remote (forwarded) SIM */
 	st_modem_sim_select_remote(ci->slot);
+	call_script(g_client, "request-sim-remote");
 
 	/* set the ATR */
 	//atr_update_csum(real_atr, sizeof(real_atr));
@@ -1072,6 +1155,7 @@
 
 	/* select remote (forwarded) SIM */
 	st_modem_reset_pulse(ci->slot, 300);
+	call_script(g_client, "request-modem-reset");
 
 	printf("Entering main loop\n");