diff --git a/controllers/api/group.go b/controllers/api/group.go
index c4bdfbeb..94d1a7b4 100644
--- a/controllers/api/group.go
+++ b/controllers/api/group.go
@@ -163,45 +163,49 @@ func (as *Server) Group(w http.ResponseWriter, r *http.Request) {
 		g = models.Group{}
 
 		//Check if content is CSV
-		var csvmode = false
 		contentType := r.Header.Get("Content-Type")
 		if strings.HasPrefix(contentType, "multipart/form-data") {
-			csvmode = true
-			targets, groupname, err := util.ParseCSV(r)
+			targets, _, err := util.ParseCSV(r)
 			if err != nil {
 				JSONResponse(w, models.Response{Success: false, Message: err.Error()}, http.StatusBadRequest)
 				return
 			}
-			// We need to fetch all the existing targets for this group, so as to not overwrite them below
-			et, _ := models.GetTargets(id)
-			g.Targets = append(targets, et...)
-			g.Name = groupname
-			g.Id = id // ID isn't supplied in the CSV file upload. Perhaps we could use the filename paramter for this? I'm not sure if this is necessary though.
-		} else { // else JSON
-			err = json.NewDecoder(r.Body).Decode(&g)
+			err = models.AddTargetsToGroup(targets, id)
 			if err != nil {
-				log.Errorf("error decoding group: %v", err)
-				JSONResponse(w, models.Response{Success: false, Message: err.Error()}, http.StatusInternalServerError)
+				log.Errorf("error add targets to group: %v", err)
+				JSONResponse(w, models.Response{Success: false, Message: "Unable to add targets to group!"}, http.StatusBadRequest)
 				return
 			}
+			// With CSV we don't return the entire target list, in line with the new pagination server side processing.
+			ng, err := models.GetGroupSummary(id, ctx.Get(r, "user_id").(int64))
+			if err != nil {
+				JSONResponse(w, models.Response{Success: false, Message: "Group not found"}, http.StatusNotFound)
+				return
+			}
+			JSONResponse(w, ng, http.StatusCreated)
+			return
 		}
+
+		// Default JSON
+		err = json.NewDecoder(r.Body).Decode(&g)
+		if err != nil {
+			log.Errorf("error decoding group: %v", err)
+			JSONResponse(w, models.Response{Success: false, Message: err.Error()}, http.StatusInternalServerError)
+			return
+		}
+
 		if g.Id != id {
 			JSONResponse(w, models.Response{Success: false, Message: "Error: /:id and group_id mismatch"}, http.StatusInternalServerError)
 			return
 		}
 		g.ModifiedDate = time.Now().UTC()
 		g.UserId = ctx.Get(r, "user_id").(int64)
+
 		err = models.PutGroup(&g)
 		if err != nil {
 			JSONResponse(w, models.Response{Success: false, Message: err.Error()}, http.StatusBadRequest)
 			return
 		}
-		// With CSV we don't return the entire target list, in line with the new pagination server side processing. To maintain backwards API capabiltiy the JSON request
-		// will still return the full list.
-		if csvmode == true {
-			JSONResponse(w, models.GroupSummary{Id: g.Id, Name: g.Name, ModifiedDate: g.ModifiedDate, NumTargets: int64(len(g.Targets))}, http.StatusCreated)
-			return
-		}
 		JSONResponse(w, g, http.StatusOK)
 	}
 }
@@ -241,7 +245,7 @@ func (as *Server) GroupTarget(w http.ResponseWriter, r *http.Request) {
 	switch {
 	case r.Method == "PUT":
 		// Add an individual target to a group
-		err = models.AddTargetToGroup(t, gid)
+		err = models.AddTargetsToGroup([]models.Target{t}, gid)
 		if err != nil {
 			JSONResponse(w, models.Response{Success: false, Message: "Unable to add target to group"}, http.StatusNotFound)
 			return
diff --git a/models/group.go b/models/group.go
index 27525953..7860ccb6 100644
--- a/models/group.go
+++ b/models/group.go
@@ -357,25 +357,53 @@ func UpdateGroup(g *Group) error {
 	return err
 }
 
-// AddTargetToGroup adds a single given target to a group by group ID
-func AddTargetToGroup(nt Target, gid int64) error {
-	// Check if target already exists in group
-	tmpt, err := GetTargetByEmail(gid, nt.Email)
+// AddTargetsToGroup adds targets to a group, updating on duplicate email
+func AddTargetsToGroup(nts []Target, gid int64) error {
+
+	// Fetch group's existing targets from database.
+	ets, err := GetTargets(gid)
 	if err != nil {
 		return err
 	}
+	// Load email to target id cache
+	existingTargetCache := make(map[string]int64, len(ets))
+	for _, t := range ets {
+		existingTargetCache[t.Email] = t.Id
+	}
+
+	// Step over each new target and see if it exists in the cache map.
+	tx := db.Begin()
+	for _, nt := range nts {
+		if _, ok := existingTargetCache[nt.Email]; ok {
+			// Update
+			nt.Id = existingTargetCache[nt.Email]
+			err = UpdateTarget(tx, nt)
+			if err != nil {
+				log.Error(err)
+				tx.Rollback()
+				return err
+			}
+		} else {
+			// Otherwise, add target if not in database
+			err = insertTargetIntoGroup(tx, nt, gid)
+			if err != nil {
+				log.Error(err)
+				tx.Rollback()
+				return err
+			}
+		}
+	} // for each new target
+
+	err = tx.Model(&Group{}).Where("id=?", gid).Update("ModifiedDate", time.Now().UTC()).Error // put this in the tx too TODO
+	if err != nil {
+		tx.Rollback()
+		return err
+	}
 
-	// If target exists in group, update it.
-	if len(tmpt) > 0 {
-		nt.Id = tmpt[0].Id
-		err = UpdateTarget(db, nt)
-	} else {
-		err = insertTargetIntoGroup(db, nt, gid)
-	}
+	err = tx.Commit().Error
 	if err != nil {
-		return err
+		tx.Rollback()
 	}
-	err = db.Model(&Group{}).Where("id=?", gid).Update("ModifiedDate", time.Now().UTC()).Error
 	return err
 }