diff --git a/fuzzterm.c b/fuzzterm.c
index 3ce8b584..667d2eea 100644
--- a/fuzzterm.c
+++ b/fuzzterm.c
@@ -82,9 +82,10 @@ void free_ctx(Context ctx) { }
 void palette_set(void *frontend, int a, int b, int c, int d) { }
 void palette_reset(void *frontend) { }
 int palette_get(void *frontend, int n, int *r, int *g, int *b) {return FALSE;}
-void write_clip(void *frontend, wchar_t *a, int *b, truecolour *c, int d, int e) { }
+void write_clip(void *frontend, int clipboard,
+                wchar_t *a, int *b, truecolour *c, int d, int e) { }
 void set_raw_mouse_mode(void *frontend, int m) { }
-void request_paste(void *frontend) { }
+void frontend_request_paste(void *frontend, int clipboard) { }
 void do_beep(void *frontend, int a) { }
 void sys_cursor(void *frontend, int x, int y) { }
 void modalfatalbox(const char *fmt, ...) { exit(0); }
diff --git a/putty.h b/putty.h
index d53eaca0..eea7fe9c 100644
--- a/putty.h
+++ b/putty.h
@@ -615,6 +615,25 @@ typedef struct truecolour {
         optionalrgb_equal((c1).fg, (c2).fg) &&  \
         optionalrgb_equal((c1).bg, (c2).bg))
 
+/*
+ * Enumeration of clipboards. CLIP_NULL is the only one provided
+ * systemwide: it's a non=clipboard, writes to which are ignored and
+ * reads from which return no data. Each platform front end extends
+ * this enumeration in its own way.
+ */
+#define CROSS_PLATFORM_CLIPBOARDS(X)            \
+    X(CLIP_NULL, "null clipboard")              \
+    /* end of list */
+
+#define ALL_CLIPBOARDS(X)                       \
+    CROSS_PLATFORM_CLIPBOARDS(X)                \
+    PLATFORM_CLIPBOARDS(X)                      \
+    /* end of list */
+
+#define CLIP_ID(id,name) id,
+enum { ALL_CLIPBOARDS(CLIP_ID) N_CLIPBOARDS };
+#undef CLIP_ID
+
 /*
  * Exports from the front end.
  */
@@ -635,7 +654,8 @@ void free_ctx(Context);
 void palette_set(void *frontend, int, int, int, int);
 void palette_reset(void *frontend);
 int palette_get(void *frontend, int n, int *r, int *g, int *b);
-void write_clip(void *frontend, wchar_t *, int *, truecolour *, int, int);
+void write_clip(void *frontend, int clipboard, wchar_t *, int *,
+                truecolour *, int, int);
 void optimised_move(void *frontend, int, int, int);
 void set_raw_mouse_mode(void *frontend, int);
 void connection_fatal(void *frontend, const char *, ...);
@@ -647,7 +667,7 @@ void modalfatalbox(const char *, ...);
 void do_beep(void *frontend, int);
 void begin_session(void *frontend);
 void sys_cursor(void *frontend, int x, int y);
-void request_paste(void *frontend);
+void frontend_request_paste(void *frontend, int clipboard);
 void frontend_keypress(void *frontend);
 void frontend_echoedit_update(void *frontend, int echo, int edit);
 /* It's the backend's responsibility to invoke this at the start of a
@@ -1051,15 +1071,16 @@ void term_mouse(Terminal *, Mouse_Button, Mouse_Button, Mouse_Action,
 		int,int,int,int,int);
 void term_key(Terminal *, Key_Sym, wchar_t *, size_t, unsigned int,
 	      unsigned int);
-void term_deselect(Terminal *);
+void term_lost_clipboard_ownership(Terminal *, int clipboard);
 void term_update(Terminal *);
 void term_invalidate(Terminal *);
 void term_blink(Terminal *, int set_cursor);
 void term_do_paste(Terminal *, const wchar_t *, int);
 void term_nopaste(Terminal *);
 int term_ldisc(Terminal *, int option);
-void term_copyall(Terminal *);
+void term_copyall(Terminal *, int clipboard);
 void term_reconfig(Terminal *, Conf *);
+void term_request_paste(Terminal *, int clipboard);
 void term_seen_key_event(Terminal *); 
 int term_data(Terminal *, int is_stderr, const char *data, int len);
 int term_data_untrusted(Terminal *, const char *data, int len);
diff --git a/terminal.c b/terminal.c
index f416e109..dd3c8548 100644
--- a/terminal.c
+++ b/terminal.c
@@ -1703,6 +1703,11 @@ Terminal *term_init(Conf *myconf, struct unicode_data *ucsdata,
     term->basic_erase_char.truecolour.bg = optionalrgb_none;
     term->erase_char = term->basic_erase_char;
 
+    /* frontends will typically overwrite these with clipboard ids they
+     * know about */
+    term->mouse_select_clipboard = CLIP_NULL;
+    term->mouse_paste_clipboard = CLIP_NULL;
+
     return term;
 }
 
@@ -5638,7 +5643,8 @@ static void clip_addchar(clip_workbuf *b, wchar_t chr, int attr, truecolour tc)
     b->bufpos++;
 }
 
-static void clipme(Terminal *term, pos top, pos bottom, int rect, int desel)
+static void clipme(Terminal *term, pos top, pos bottom, int rect, int desel,
+                   int clipboard)
 {
     clip_workbuf buf;
     int old_top_x;
@@ -5799,13 +5805,14 @@ static void clipme(Terminal *term, pos top, pos bottom, int rect, int desel)
     clip_addchar(&buf, 0, 0, term->basic_erase_char.truecolour);
 #endif
     /* Finally, transfer all that to the clipboard. */
-    write_clip(term->frontend, buf.textbuf, buf.attrbuf, buf.tcbuf, buf.bufpos, desel);
+    write_clip(term->frontend, clipboard,
+               buf.textbuf, buf.attrbuf, buf.tcbuf, buf.bufpos, desel);
     sfree(buf.textbuf);
     sfree(buf.attrbuf);
     sfree(buf.tcbuf);
 }
 
-void term_copyall(Terminal *term)
+void term_copyall(Terminal *term, int clipboard)
 {
     pos top;
     pos bottom;
@@ -5814,7 +5821,14 @@ void term_copyall(Terminal *term)
     top.x = 0;
     bottom.y = find_last_nonempty_line(term, screen);
     bottom.x = term->cols;
-    clipme(term, top, bottom, 0, TRUE);
+    clipme(term, top, bottom, 0, TRUE, clipboard);
+}
+
+void term_request_paste(Terminal *term, int clipboard)
+{
+    if (clipboard == CLIP_NULL)
+        return;
+    frontend_request_paste(term->frontend, clipboard);
 }
 
 /*
@@ -6397,7 +6411,8 @@ void term_mouse(Terminal *term, Mouse_Button braw, Mouse_Button bcooked,
 	     * data to the clipboard.
 	     */
 	    clipme(term, term->selstart, term->selend,
-		   (term->seltype == RECTANGULAR), FALSE);
+		   (term->seltype == RECTANGULAR), FALSE,
+                   term->mouse_select_clipboard);
 	    term->selstate = SELECTED;
 	} else
 	    term->selstate = NO_SELECTION;
@@ -6407,7 +6422,7 @@ void term_mouse(Terminal *term, Mouse_Button braw, Mouse_Button bcooked,
 		   || a == MA_2CLK || a == MA_3CLK
 #endif
 		   )) {
-	request_paste(term->frontend);
+	term_request_paste(term, term->mouse_paste_clipboard);
     }
 
     /*
@@ -6471,8 +6486,11 @@ static void deselect(Terminal *term)
     term->selstart.x = term->selstart.y = term->selend.x = term->selend.y = 0;
 }
 
-void term_deselect(Terminal *term)
+void term_lost_clipboard_ownership(Terminal *term, int clipboard)
 {
+    if (clipboard != term->mouse_select_clipboard)
+        return;
+
     deselect(term);
     term_update(term);
 
diff --git a/terminal.h b/terminal.h
index 03659744..8cb56f6f 100644
--- a/terminal.h
+++ b/terminal.h
@@ -327,6 +327,9 @@ struct terminal_tag {
     int scroll_on_key;
     int xterm_256_colour;
     int true_colour;
+
+    int mouse_select_clipboard;
+    int mouse_paste_clipboard;
 };
 
 #define in_utf(term) ((term)->utf || (term)->ucsdata->line_codepage==CP_UTF8)
diff --git a/unix/gtkapp.c b/unix/gtkapp.c
index d1861b1e..57358dcb 100644
--- a/unix/gtkapp.c
+++ b/unix/gtkapp.c
@@ -147,7 +147,7 @@ static void paste_cb(GSimpleAction *action,
                      GVariant      *parameter,
                      gpointer       user_data)
 {
-    request_paste(user_data);
+    paste_menu_action(user_data);
 }
 
 static const GActionEntry win_actions[] = {
diff --git a/unix/gtkwin.c b/unix/gtkwin.c
index 96421ac5..99144557 100644
--- a/unix/gtkwin.c
+++ b/unix/gtkwin.c
@@ -1022,7 +1022,7 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
 #ifdef KEY_EVENT_DIAGNOSTICS
             debug((" - Shift-Insert paste\n"));
 #endif
-	    request_paste(inst);
+	    term_request_paste(inst->term, CLIP_SYSTEM);
 	    return TRUE;
 	}
 
@@ -2532,15 +2532,16 @@ static void clipboard_clear(GtkClipboard *clipboard, gpointer data)
     struct gui_data *inst = cdi->inst;
 
     if (inst->current_cdi == cdi) {
-        term_deselect(inst->term);
+        term_lost_clipboard_ownership(inst->term, CLIP_SYSTEM);
         inst->current_cdi = NULL;
     }
     sfree(cdi->pasteout_data_utf8);
     sfree(cdi);
 }
 
-void write_clip(void *frontend, wchar_t *data, int *attr, truecolour *truecolour,
-                int len, int must_deselect)
+void write_clip(void *frontend, int clipboard,
+                char_t *data, int *attr, truecolour *truecolour, int len,
+                int must_deselect)
 {
     struct gui_data *inst = (struct gui_data *)frontend;
     struct clipboard_data_instance *cdi;
@@ -2609,9 +2610,10 @@ static void clipboard_text_received(GtkClipboard *clipboard,
     sfree(paste);
 }
 
-void request_paste(void *frontend)
+void frontend_request_paste(void *frontend, int clipboard)
 {
     struct gui_data *inst = (struct gui_data *)frontend;
+    assert(clipboard == CLIP_SYSTEM);
     gtk_clipboard_request_text(inst->clipboard, clipboard_text_received, inst);
 }
 
@@ -2667,8 +2669,9 @@ static char *retrieve_cutbuffer(int *nbytes)
 #endif
 }
 
-void write_clip(void *frontend, wchar_t *data, int *attr, truecolour *truecolour,
-                int len, int must_deselect)
+void write_clip(void *frontend, int clipboard,
+                wchar_t *data, int *attr, truecolour *truecolour, int len,
+                int must_deselect)
 {
     struct gui_data *inst = (struct gui_data *)frontend;
     if (inst->pasteout_data)
@@ -2763,7 +2766,7 @@ void write_clip(void *frontend, wchar_t *data, int *attr, truecolour *truecolour
     }
 
     if (must_deselect)
-	term_deselect(inst->term);
+	term_lost_clipboard_ownership(inst->term, clipboard);
 }
 
 static void selection_get(GtkWidget *widget, GtkSelectionData *seldata,
@@ -2790,7 +2793,7 @@ static gint selection_clear(GtkWidget *widget, GdkEventSelection *seldata,
 {
     struct gui_data *inst = (struct gui_data *)data;
 
-    term_deselect(inst->term);
+    term_lost_clipboard_ownership(inst->term, CLIP_SYSTEM);
     if (inst->pasteout_data)
 	sfree(inst->pasteout_data);
     if (inst->pasteout_data_ctext)
@@ -2806,9 +2809,12 @@ static gint selection_clear(GtkWidget *widget, GdkEventSelection *seldata,
     return TRUE;
 }
 
-void request_paste(void *frontend)
+void frontend_request_paste(void *frontend, int clipboard)
 {
     struct gui_data *inst = (struct gui_data *)frontend;
+
+    assert(clipboard == CLIP_SYSTEM);
+
     /*
      * In Unix, pasting is asynchronous: all we can do at the
      * moment is to call gtk_selection_convert(), and when the data
@@ -3007,6 +3013,12 @@ void init_clipboard(struct gui_data *inst)
 
 #endif /* JUST_USE_GTK_CLIPBOARD_UTF8 */
 
+void paste_menu_action(void *frontend)
+{
+    struct gui_data *inst = (struct gui_data *)frontend;
+    term_request_paste(inst->term, CLIP_SYSTEM);
+}
+
 static void set_window_titles(struct gui_data *inst)
 {
     /*
@@ -4048,7 +4060,7 @@ void reset_terminal_menuitem(GtkMenuItem *item, gpointer data)
 void copy_all_menuitem(GtkMenuItem *item, gpointer data)
 {
     struct gui_data *inst = (struct gui_data *)data;
-    term_copyall(inst->term);
+    term_copyall(inst->term, CLIP_SYSTEM);
 }
 
 void special_menuitem(GtkMenuItem *item, gpointer data)
@@ -4922,6 +4934,8 @@ void new_session_window(Conf *conf, const char *geometry_string)
     inst->eventlogstuff = eventlogstuff_new();
 
     inst->term = term_init(inst->conf, &inst->ucsdata, inst);
+    inst->term->mouse_select_clipboard = CLIP_SYSTEM;
+    inst->term->mouse_paste_clipboard = CLIP_SYSTEM;
     inst->logctx = log_init(inst, inst->conf);
     term_provide_logctx(inst->term, inst->logctx);
 
diff --git a/unix/unix.h b/unix/unix.h
index bedb28d0..6c9d11c7 100644
--- a/unix/unix.h
+++ b/unix/unix.h
@@ -119,6 +119,10 @@ unsigned long getticks(void);
  */
 #define FLAG_STDERR_TTY 0x1000
 
+#define PLATFORM_CLIPBOARDS(X)                      \
+    X(CLIP_SYSTEM, "system clipboard")              \
+    /* end of list */
+
 /* The per-session frontend structure managed by gtkwin.c */
 struct gui_data;
 
@@ -143,6 +147,9 @@ GtkWidget *make_gtk_toplevel_window(void *frontend);
 /* Defined in gtkcomm.c */
 void gtkcomm_setup(void);
 
+/* Defined in gtkwin.c */
+void paste_menu_action(void *frontend);
+
 /* Things pty.c needs from pterm.c */
 const char *get_x_display(void *frontend);
 int font_dimension(void *frontend, int which);/* 0 for width, 1 for height */
diff --git a/windows/windlg.c b/windows/windlg.c
index 8bd02d85..39d2addd 100644
--- a/windows/windlg.c
+++ b/windows/windlg.c
@@ -140,7 +140,7 @@ static INT_PTR CALLBACK LogProc(HWND hwnd, UINT msg,
 			    memcpy(p, sel_nl, sizeof(sel_nl));
 			    p += sizeof(sel_nl);
 			}
-			write_aclip(NULL, clipdata, size, TRUE);
+			write_aclip(NULL, CLIP_SYSTEM, clipdata, size, TRUE);
 			sfree(clipdata);
 		    }
 		    sfree(selitems);
diff --git a/windows/window.c b/windows/window.c
index 3a67fb87..b8452757 100644
--- a/windows/window.c
+++ b/windows/window.c
@@ -637,6 +637,8 @@ int WINAPI WinMain(HINSTANCE inst, HINSTANCE prev, LPSTR cmdline, int show)
      * timer_change_notify() which will expect hwnd to exist.)
      */
     term = term_init(conf, &ucsdata, NULL);
+    term->mouse_select_clipboard = CLIP_SYSTEM;
+    term->mouse_paste_clipboard = CLIP_SYSTEM;
     logctx = log_init(NULL, conf);
     term_provide_logctx(term, logctx);
     term_size(term, conf_get_int(conf, CONF_height),
@@ -2328,10 +2330,10 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT message,
 	    }
 	    break;
 	  case IDM_COPYALL:
-	    term_copyall(term);
+	    term_copyall(term, CLIP_SYSTEM);
 	    break;
 	  case IDM_PASTE:
-	    request_paste(NULL);
+	    term_request_paste(term, CLIP_SYSTEM);
 	    break;
 	  case IDM_CLRSB:
 	    term_clrsb(term);
@@ -2563,7 +2565,7 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT message,
 	break;
       case WM_DESTROYCLIPBOARD:
 	if (!ignore_clip)
-	    term_deselect(term);
+	    term_lost_clipboard_ownership(term, CLIP_SYSTEM);
 	ignore_clip = FALSE;
 	return 0;
       case WM_PAINT:
@@ -4146,7 +4148,7 @@ static int TranslateKey(UINT message, WPARAM wParam, LPARAM lParam,
 	    return 0;
 	}
 	if (wParam == VK_INSERT && shift_state == 1) {
-	    request_paste(NULL);
+	    term_request_paste(term, CLIP_SYSTEM);
 	    return 0;
 	}
 	if (left_alt && wParam == VK_F4 && conf_get_int(conf, CONF_alt_f4)) {
@@ -4861,11 +4863,15 @@ void palette_reset(void *frontend)
     }
 }
 
-void write_aclip(void *frontend, char *data, int len, int must_deselect)
+void write_aclip(void *frontend, int clipboard,
+                 char *data, int len, int must_deselect)
 {
     HGLOBAL clipdata;
     void *lock;
 
+    if (clipboard != CLIP_SYSTEM)
+        return;
+
     clipdata = GlobalAlloc(GMEM_DDESHARE | GMEM_MOVEABLE, len + 1);
     if (!clipdata)
 	return;
@@ -4905,13 +4911,17 @@ int cmpCOLORREF(void *va, void *vb)
 /*
  * Note: unlike write_aclip() this will not append a nul.
  */
-void write_clip(void *frontend, wchar_t *data, int *attr, truecolour *truecolour,
-                int len, int must_deselect)
+void write_clip(void *frontend, int clipboard,
+                wchar_t *data, int *attr, truecolour *truecolour, int len,
+                int must_deselect)
 {
     HGLOBAL clipdata, clipdata2, clipdata3;
     int len2;
     void *lock, *lock2, *lock3;
 
+    if (clipboard != CLIP_SYSTEM)
+        return;
+
     len2 = WideCharToMultiByte(CP_ACP, 0, data, len, 0, 0, NULL, NULL);
 
     clipdata = GlobalAlloc(GMEM_DDESHARE | GMEM_MOVEABLE,
@@ -5372,8 +5382,10 @@ static void process_clipdata(HGLOBAL clipdata, int unicode)
     sfree(clipboard_contents);
 }
 
-void request_paste(void *frontend)
+void frontend_request_paste(void *frontend, int clipboard)
 {
+    assert(clipboard == CLIP_SYSTEM);
+
     /*
      * I always thought pasting was synchronous in Windows; the
      * clipboard access functions certainly _look_ synchronous,
diff --git a/windows/winstuff.h b/windows/winstuff.h
index 0b535822..39ff9426 100644
--- a/windows/winstuff.h
+++ b/windows/winstuff.h
@@ -55,6 +55,10 @@ struct FontSpec *fontspec_new(const char *name,
 #define PLATFORM_IS_UTF16 /* enable UTF-16 processing when exchanging
 			   * wchar_t strings with environment */
 
+#define PLATFORM_CLIPBOARDS(X)                      \
+    X(CLIP_SYSTEM, "system clipboard")              \
+    /* end of list */
+
 /*
  * Where we can, we use GetWindowLongPtr and friends because they're
  * more useful on 64-bit platforms, but they're a relatively recent
@@ -247,7 +251,7 @@ GLOBAL void *logctx;
  * which takes the data string in the system code page instead of
  * Unicode.
  */
-void write_aclip(void *frontend, char *, int, int);
+void write_aclip(void *frontend, int clipboard, char *, int, int);
 
 #define WM_NETEVENT  (WM_APP + 5)