diff --git a/CHANGELOG.md b/CHANGELOG.md
index 096bed5f..2bfe409d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 All notable changes to the ZSS package will be documented in this file.
 
+## `3.1.0`
+- Enhancement: module registry (#732)
+
 ## `3.0.0`
 - Enhancement: if no `zowe.logDirectory` is defined in config, logging is disabled. (#726)
 - Bugfix: Support cross-memory server parameters longer than 128 characters (#684)
diff --git a/build/build_dynamic.sh b/build/build_dynamic.sh
index 4167e749..1514ac62 100755
--- a/build/build_dynamic.sh
+++ b/build/build_dynamic.sh
@@ -50,12 +50,15 @@ xlc -S -M -qmetal -q64 -DSUBPOOL=132 -DMETTLE=1 -DMSGPREFIX=\"ZWE\" \
   -DZISDYN_REVISION="$micro" \
   -DZISDYN_VERSION_DATE_STAMP="$date_stamp" \
   -DZISDYN_PLUGIN_VERSION=${DYNLINK_PLUGIN_VERSION} \
+  -DLPA_LOG_DEBUG_MSG_ID=\"ZWES0100I\" \
+  -DMODREG_LOG_DEBUG_MSG_ID=\"ZWES0100I\" \
   -qreserved_reg=r12 \
   -DRCVR_CPOOL_STATES \
   -DHAVE_METALIO=1 \
   -Wc,langlvl\(extc99\),arch\(8\),agg,exp,list\(\),so\(\),off,xref,roconst,longname,lp64 \
   -I ${COMMON}/h -I ${ZSS}/h \
   -I ${ZSS}/zis-aux/include -I ${ZSS}/zis-aux/src \
+  -I /usr/include/zos \
   ${ZSS}/c/zis/zisdynamic.c \
   ${ZSS}/c/zis/server-api.c \
   ${ZSS}/c/zis/client.c \
@@ -81,6 +84,7 @@ xlc -S -M -qmetal -q64 -DSUBPOOL=132 -DMETTLE=1 -DMSGPREFIX=\"ZWE\" \
   ${COMMON}/c/logging.c \
   ${COMMON}/c/lpa.c \
   ${COMMON}/c/metalio.c \
+  ${COMMON}/c/modreg.c \
   ${COMMON}/c/nametoken.c \
   ${COMMON}/c/pause-element.c \
   ${COMMON}/c/pc.c \
@@ -125,6 +129,7 @@ for file in \
     logging \
     lpa \
     metalio \
+    modreg \
     nametoken \
     pause-element \
     pc \
@@ -173,6 +178,7 @@ le.o \
 logging.o \
 lpa.o \
 metalio.o \
+modreg.o \
 nametoken.o \
 pause-element.o \
 pc.o \
diff --git a/build/build_zis.sh b/build/build_zis.sh
index 71bf1b73..70d6e468 100755
--- a/build/build_zis.sh
+++ b/build/build_zis.sh
@@ -56,9 +56,12 @@ xlc -S -M -qmetal -q64 -DSUBPOOL=132 -DMETTLE=1 -DMSGPREFIX=\"ZWE\" \
   -DZIS_VERSION_DATE_STAMP="$date_stamp" \
   -DRADMIN_XMEM_MODE \
   -DRCVR_CPOOL_STATES \
+  -DLPA_LOG_DEBUG_MSG_ID=\"ZWES0100I\" \
+  -DMODREG_LOG_DEBUG_MSG_ID=\"ZWES0100I\" \
   -qreserved_reg=r12 \
   -Wc,arch\(8\),agg,exp,list\(\),so\(\),off,xref,roconst,longname,lp64 \
   -I ${COMMON}/h -I ${ZSS}/h -I ${ZSS}/zis-aux/include -I ${ZSS}/zis-aux/src \
+  -I /usr/include/zos \
    ${COMMON}/c/alloc.c \
    ${COMMON}/c/as.c \
    ${COMMON}/c/cellpool.c \
@@ -70,6 +73,7 @@ xlc -S -M -qmetal -q64 -DSUBPOOL=132 -DMETTLE=1 -DMSGPREFIX=\"ZWE\" \
    ${COMMON}/c/logging.c \
    ${COMMON}/c/lpa.c \
    ${COMMON}/c/metalio.c \
+   ${COMMON}/c/modreg.c \
    ${COMMON}/c/mtlskt.c \
    ${COMMON}/c/nametoken.c \
    ${COMMON}/c/pause-element.c \
@@ -102,7 +106,7 @@ xlc -S -M -qmetal -q64 -DSUBPOOL=132 -DMETTLE=1 -DMSGPREFIX=\"ZWE\" \
    ${ZSS}/zis-aux/src/aux-host.c
 
 for file in \
-    alloc as cellpool cmutils collections crossmemory isgenq le logging lpa metalio mtlskt nametoken \
+    alloc as cellpool cmutils collections crossmemory isgenq le logging lpa metalio modreg mtlskt nametoken \
     pause-element pc qsam radmin recovery resmgr scheduling shrmem64 stcbase timeutls utils xlate \
     zos zvt \
     parm plugin server server-api service \
@@ -125,6 +129,7 @@ ld -V -b ac=1 -b rent -b case=mixed -b map -b xref -b reus \
   logging.o \
   lpa.o \
   metalio.o \
+  modreg.o \
   mtlskt.o \
   nametoken.o \
   qsam.o \
@@ -165,6 +170,7 @@ ld -V -b ac=1 -b rent -b case=mixed -b map -b xref -b reus \
   logging.o \
   lpa.o \
   metalio.o \
+  modreg.o \
   mtlskt.o \
   nametoken.o \
   pause-element.o \
diff --git a/c/zis/server-api.c b/c/zis/server-api.c
index a8d59223..2910d466 100644
--- a/c/zis/server-api.c
+++ b/c/zis/server-api.c
@@ -31,6 +31,10 @@ _Bool zisIsLPADevModeOn(const ZISContext *context) {
   return (context->cmsFlags & devFlags) || ZIS_LPA_DEV_MODE;
 }
 
+_Bool zisIsModregOn(const ZISContext *context) {
+  return context->cmsFlags & CMS_SERVER_FLAG_USE_MODREG;
+}
+
 void zisGetServerVersion(int *major, int *minor, int *revision) {
   *major = -1;
   *minor = -1;
diff --git a/c/zis/server.c b/c/zis/server.c
index 31744d26..a019d3d2 100644
--- a/c/zis/server.c
+++ b/c/zis/server.c
@@ -32,6 +32,7 @@
 #include "stcbase.h"
 #include "utils.h"
 #include "recovery.h"
+#include "modreg.h"
 
 #include "zis/message.h"
 #include "zis/parm.h"
@@ -82,6 +83,9 @@ See details in the ZSS Cross Memory Server installation guide
 #define ZIS_PARM_DEV_MODE_LPA                 CMS_PROD_ID".DEV_MODE.LPA"
   #define ZIS_PARM_DEV_MODE_ON                  "YES"
 
+#define ZIS_PARM_MODREG                       CMS_PROD_ID".MODULE_REGISTRY"
+  #define ZIS_PARM_MODREG_OFF                   "NO"
+
 #define ZIS_PARMLIB_PARM_SERVER_NAME          CMS_PROD_ID".NAME"
 
 #define ZIS_DYN_LINKAGE_PLUGIN_MOD_SUFFIX     "ISDL"
@@ -676,18 +680,49 @@ static int relocatePluginToLPAIfNeeded(ZISContext *context,
   /* Check if LPA, and load if needed */
   if (lpaNeeded) {
 
+    const char *status = "n/a";
+
     if (!lpaPresent) {
 
       EightCharString ddname = {"STEPLIB "};
-      int lpaRSN = 0;
-      int lpaRC = lpaAdd(&anchor->moduleInfo, &ddname, &moduleName, &lpaRSN);
-      if (lpaRC != 0) {
-        zowelog(NULL, LOG_COMP_ID_CMS, ZOWE_LOG_SEVERE, ZIS_LOG_LPA_FAILURE_MSG,
-                "ADD", anchor->moduleInfo.inputInfo.name, lpaRC, lpaRSN);
-        return RC_ZIS_ERROR;
+
+      if (zisIsModregOn(context) && !zisIsLPADevModeOn(context)) {
+        uint64_t modregRSN;
+        int modregRC = modregRegister(ddname, moduleName, &anchor->moduleInfo,
+                                      &modregRSN);
+        if (modregRC == RC_MODREG_OK) {
+          status = "new instance added to registry";
+          lpaPresent = true;
+        } else if (modregRC == RC_MODREG_ALREADY_REGISTERED) {
+          status = "existing instance reused from registry";
+          lpaPresent = true;
+        }  else if (modregRC == RC_MODREG_MARK_MISSING) {
+          zowelog(NULL, LOG_COMP_ID_CMS, ZOWE_LOG_INFO,
+                  ZIS_LOG_MODREG_NO_MARK_MSG, moduleName.text);
+        } else {
+          zowelog(NULL, LOG_COMP_ID_CMS, ZOWE_LOG_SEVERE,
+                  ZIS_LOG_MODREG_FAILURE_MSG, moduleName.text,
+                  modregRC, modregRSN);
+          return RC_ZIS_ERROR;
+        }
+      }
+
+      if (!lpaPresent) {
+        int lpaRSN = 0;
+        int lpaRC = lpaAdd(&anchor->moduleInfo, &ddname, &moduleName, &lpaRSN);
+        if (lpaRC == 0) {
+          status = "own instance loaded to LPA";
+        } else {
+          zowelog(NULL, LOG_COMP_ID_CMS, ZOWE_LOG_SEVERE,
+                  ZIS_LOG_LPA_FAILURE_MSG,
+                  "ADD", moduleName.text, lpaRC, lpaRSN);
+          return RC_ZIS_ERROR;
+        }
       }
 
       anchor->flags |= ZIS_PLUGIN_ANCHOR_FLAG_LPA;
+    } else {
+      status = "previously added/loaded instance reused";
     }
 
     /* Invoke EP to get relocated services */
@@ -699,6 +734,16 @@ static int relocatePluginToLPAIfNeeded(ZISContext *context,
 
     *pluginAddr = getPluginDescriptor();
 
+    zowelog(NULL, LOG_COMP_ID_CMS, ZOWE_LOG_INFO,
+            ZIS_LOG_MODULE_STATUS_MSG" (%p)", moduleName.text, status,
+            lpaInfo->outputInfo.stuff.successInfo.loadPointAddr);
+
+  } else {
+
+    zowelog(NULL, LOG_COMP_ID_CMS, ZOWE_LOG_INFO,
+            ZIS_LOG_MODULE_STATUS_MSG, moduleName.text,
+            "private storage instance used");
+
   }
 
   return RC_ZIS_OK;
@@ -1443,7 +1488,7 @@ static int loadConfig(ZISContext *context,
 
 static int getCMSConfigFlags(const ZISParmSet *zisParms) {
 
-  int flags = CMS_SERVER_FLAG_NONE;
+  int flags = CMS_SERVER_FLAG_USE_MODREG;
 
   const char *coldStartValue = zisGetParmValue(zisParms, ZIS_PARM_COLD_START);
   if (coldStartValue && strlen(coldStartValue) == 0) {
@@ -1475,6 +1520,11 @@ static int getCMSConfigFlags(const ZISParmSet *zisParms) {
     flags |= CMS_SERVER_FLAG_RESET_LOOKUP;
   }
 
+  const char *modregMode = zisGetParmValue(zisParms, ZIS_PARM_MODREG);
+  if (modregMode && !strcmp(modregMode, ZIS_PARM_MODREG_OFF)) {
+    flags &= ~CMS_SERVER_FLAG_USE_MODREG;
+  }
+
   return flags;
 }
 
diff --git a/c/zis/stubinit.c b/c/zis/stubinit.c
index ee83deb3..c8123800 100644
--- a/c/zis/stubinit.c
+++ b/c/zis/stubinit.c
@@ -12,6 +12,7 @@
     stubVector[ZIS_STUB_ZISDYNPV] = (void*)zisdynGetPluginVersion;
     stubVector[ZIS_STUB_ZISGVRSN] = (void*)zisGetServerVersion;
     stubVector[ZIS_STUB_ZISLPADV] = (void*)zisIsLPADevModeOn;
+    stubVector[ZIS_STUB_ZISMDREG] = (void*)zisIsModregOn;
     stubVector[ZIS_STUB_ZISCSRVC] = (void*)zisCallService;
     stubVector[ZIS_STUB_ZISCUSVC] = (void*)zisCallServiceUnchecked;
     stubVector[ZIS_STUB_ZISCVSVC] = (void*)zisCallVersionedService;
@@ -558,6 +559,7 @@
     stubVector[ZIS_STUB_ZVTFENTR] = (void*)zvtFreeEntry;
     stubVector[ZIS_STUB_ZVTGXMLR] = (void*)zvtGetCMSLookupRoutineAnchor;
     stubVector[ZIS_STUB_ZVTSXMLR] = (void*)zvtSetCMSLookupRoutineAnchor;
+    stubVector[ZIS_STUB_MODRRGST] = (void*)modregRegister;
 /*
   This program and the accompanying materials are
   made available under the terms of the Eclipse Public License v2.0 which accompanies
diff --git a/c/zis/zisdynamic.c b/c/zis/zisdynamic.c
index 4c933f2d..600e94c1 100644
--- a/c/zis/zisdynamic.c
+++ b/c/zis/zisdynamic.c
@@ -31,6 +31,7 @@
 #include "logging.h"
 #include "lpa.h"
 #include "metalio.h"
+#include "modreg.h"
 #include "nametoken.h"
 #include "pause-element.h"
 #include "pc.h"
@@ -423,6 +424,8 @@ static int verifyZISVersion(void) {
 
 ZISPlugin *getPluginDescriptor(void) {
 
+  MODREG_MARK_MODULE();
+
   if (verifyZISVersion() != 0) {
     return NULL;
   }
diff --git a/deps/zowe-common-c b/deps/zowe-common-c
index d5372ea3..5fc78742 160000
--- a/deps/zowe-common-c
+++ b/deps/zowe-common-c
@@ -1 +1 @@
-Subproject commit d5372ea381853cd5ed95a141c7a9b0b0d7cbf271
+Subproject commit 5fc7874238a2aebe6a476d628868cc03e8edb48e
diff --git a/h/zis/message.h b/h/zis/message.h
index 277a90f4..ebe0f2ca 100644
--- a/h/zis/message.h
+++ b/h/zis/message.h
@@ -116,6 +116,18 @@
 #define ZIS_LOG_CXMS_MOD_NAME_FAILED_MSG_TEXT   "ZSS Cross-Memory server module member name not determined, RC = %d"
 #define ZIS_LOG_CXMS_MOD_NAME_FAILED_MSG        ZIS_LOG_CXMS_MOD_NAME_FAILED_MSG_ID" "ZIS_LOG_CXMS_MOD_NAME_FAILED_MSG_TEXT
 
+#define ZIS_LOG_MODULE_STATUS_MSG_ID            ZIS_MSG_PRFX"0022I"
+#define ZIS_LOG_MODULE_STATUS_MSG_TEXT          "Module %-8.8s status: %s"
+#define ZIS_LOG_MODULE_STATUS_MSG               ZIS_LOG_MODULE_STATUS_MSG_ID" "ZIS_LOG_MODULE_STATUS_MSG_TEXT
+
+#define ZIS_LOG_MODREG_NO_MARK_MSG_ID           ZIS_MSG_PRFX"0023I"
+#define ZIS_LOG_MODREG_NO_MARK_MSG_TEXT         "Module %-8.8s not eligible for registry, proceeding with LPA ADD"
+#define ZIS_LOG_MODREG_NO_MARK_MSG              ZIS_LOG_MODREG_NO_MARK_MSG_ID" "ZIS_LOG_MODREG_NO_MARK_MSG_TEXT
+
+#define ZIS_LOG_MODREG_FAILURE_MSG_ID           ZIS_MSG_PRFX"0024E"
+#define ZIS_LOG_MODREG_FAILURE_MSG_TEXT         "Module %-8.8s not registered, RC = %d, RSN = 0x%016llX"
+#define ZIS_LOG_MODREG_FAILURE_MSG              ZIS_LOG_MODREG_FAILURE_MSG_ID" "ZIS_LOG_MODREG_FAILURE_MSG_TEXT
+
 /* ZIS AUX messages */
 
 #define ZISAUX_LOG_STARTUP_MSG_ID               ZIS_MSG_PRFX"0050I"
diff --git a/h/zis/server-api.h b/h/zis/server-api.h
index d0fb0749..8178dd57 100644
--- a/h/zis/server-api.h
+++ b/h/zis/server-api.h
@@ -18,6 +18,7 @@
 
 #pragma map(zisGetServerVersion, "ZISGVRSN")
 #pragma map(zisIsLPADevModeOn, "ZISLPADV")
+#pragma map(zisIsModregOn, "ZISMDREG")
 
 /**
  * Get the version of ZIS. In case of failure, all the results are set to -1.
@@ -36,6 +37,13 @@ struct ZISContext_tag;
  */
 _Bool zisIsLPADevModeOn(const struct ZISContext_tag *context);
 
+/**
+ * Check if the module registry is enabled for ZIS.
+ * @param[in] context The server context.
+ * @return @c true if on, otherwise @c false.
+ */
+_Bool zisIsModregOn(const struct ZISContext_tag *context);
+
 #endif /* ZIS_SERVER_API_H_ */
 
 /*
diff --git a/h/zis/zisstubs.h b/h/zis/zisstubs.h
index 449ae7b9..9aef5819 100644
--- a/h/zis/zisstubs.h
+++ b/h/zis/zisstubs.h
@@ -20,7 +20,7 @@
    FULL BACKWARD COMPATIBILITY MUST BE MAINTAINED
    */
 
-#define ZIS_STUBS_VERSION 4
+#define ZIS_STUBS_VERSION 5
 
 /*
   How does a user check for compatibility?
@@ -48,6 +48,7 @@
 #define ZIS_STUB_ZISDYNPV 2 /* zisdynGetPluginVersion mapped */
 #define ZIS_STUB_ZISGVRSN 3 /* zisGetServerVersion mapped */
 #define ZIS_STUB_ZISLPADV 4 /* zisIsLPADevModeOn mapped */
+#define ZIS_STUB_ZISMDREG 5 /* zisIsModregOn mapped */
 
 /* zis/client, 50-79 */
 #define ZIS_STUB_ZISCSRVC 50 /* zisCallService */
@@ -693,6 +694,9 @@
 #define ZIS_STUB_ZVTGXMLR 904 /* zvtGetCMSLookupRoutineAnchor mapped */
 #define ZIS_STUB_ZVTSXMLR 905 /* zvtSetCMSLookupRoutineAnchor mapped */
 
+/* modreg, 915-920 */
+#define ZIS_STUB_MODRRGST 915 /* modregRegister mapped */
+
 #endif /* ZIS_ZISSTUBS_H_ */
 
 /*
diff --git a/samplib/zis/ZWESIP00 b/samplib/zis/ZWESIP00
index f1f600ca..945beda2 100644
--- a/samplib/zis/ZWESIP00
+++ b/samplib/zis/ZWESIP00
@@ -53,7 +53,13 @@
 //*         AT START UP. THIS MODE MUST NEVER BE USED IN PRODUCTION  */
 //*         AS IT MAY AFFECT THE CALLERS OF THE CROSS-MEMORY SERVER. */
 //*         USE THIS MODE TO DECREASE THE MEMORY FOOTPRINT DURING    */
-//*         DEVELOPMENT.                                             */
+//*         DEVELOPMENT. ADDITIONALLY, THIS MODE WILL DISABLE THE    */
+//*         MODULE REGISTRY FEATURE BECAUSE ZIS CANNOT REMOVE SHARED */
+//*         MODULE FROM LPA.                                         */
+//*     MODULE_REGISTRY - MODULE REGISTRY MODE. DEFAULT IS YES. IF   */
+//*         SET TO NO, DISABLES THE MODULE REGISTRY FEATURE, SO THAT */
+//*         ZIS WILL ALWAYS USE ITS OWN INSTANCES OF LOAD MODULES IN */
+//*         LPA.                                                     */
 //*                                                                  */
 //********************************************************************/