diff --git a/docs/NEWS.md b/docs/NEWS.md
index b00e3872..56841b76 100644
--- a/docs/NEWS.md
+++ b/docs/NEWS.md
@@ -12,6 +12,13 @@ See [UPGRADING.md](UPGRADING.md) for more detailed instructions about upgrading
 
 ## New features
 
+### SpaceCadet "no-delay" mode
+
+SpaceCadet can now be enabled in "no-delay" mode, wherein the primary (modifier)
+value of the key will be sent to the host immediately when the key is pressed.
+If the SpaceCadet key is released before the timeout, the modifier is released,
+and then the alternate (symbol) value is sent.  To activate "no-delay" mode, call `SpaceCadet.enableWithoutDelay()`.
+
 ### New Qukeys features
 
 #### Tap-repeat
diff --git a/plugins/Kaleidoscope-SpaceCadet/README.md b/plugins/Kaleidoscope-SpaceCadet/README.md
index 4b6a0574..bae8ea0c 100644
--- a/plugins/Kaleidoscope-SpaceCadet/README.md
+++ b/plugins/Kaleidoscope-SpaceCadet/README.md
@@ -133,6 +133,13 @@ properties:
 > is disabled. This is useful for interfacing with other plugins or macros,
 > especially where SpaceCadet functionality isn't always desired.
 
+### `.enableWithoutDelay()`
+
+> This method enables the SpaceCadet plugin in "no-delay" mode. In this mode,
+> SpaceCadet immediately sends the primary (modifier) value of the SpaceCadet
+> key when it is pressed. If it is then released before timing out, it sends the
+> alternate "tap" value, replacing the modifier.
+
 ### `Key_SpaceCadetEnable`
 
 > This provides a key for placing on a keymap for enabling the SpaceCadet
diff --git a/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.cpp b/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.cpp
index 6135c320..b3fd2edb 100644
--- a/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.cpp
+++ b/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.cpp
@@ -46,7 +46,7 @@ uint16_t SpaceCadet::time_out = 200;
 // -----------------------------------------------------------------------------
 // State variables
 
-bool SpaceCadet::disabled = false;
+uint8_t SpaceCadet::mode_ = SpaceCadet::Mode::ON;
 
 // These variables are used to keep track of any pending unresolved SpaceCadet
 // key that has been pressed. If `pending_map_index_` is negative, it means
@@ -78,23 +78,6 @@ SpaceCadet::SpaceCadet() {
   map = initialmap;
 }
 
-// -----------------------------------------------------------------------------
-// Function to determine whether SpaceCadet is active (useful for Macros and
-// other plugins).
-bool SpaceCadet::active() {
-  return !disabled;
-}
-
-// Function to enable SpaceCadet behavior
-void SpaceCadet::enable() {
-  disabled = false;
-}
-
-// Function to disable SpaceCadet behavior
-void SpaceCadet::disable() {
-  disabled = true;
-}
-
 // =============================================================================
 // Event handler hook functions
 
@@ -134,7 +117,7 @@ EventHandlerResult SpaceCadet::onKeyswitchEvent(KeyEvent &event) {
   }
 
   // Do nothing if disabled, but keep the event tracker current.
-  if (disabled)
+  if (mode_ == Mode::OFF)
     return EventHandlerResult::OK;
 
   if (!event_queue_.isEmpty()) {
@@ -162,7 +145,13 @@ EventHandlerResult SpaceCadet::onKeyswitchEvent(KeyEvent &event) {
     // Check for a SpaceCadet key
     pending_map_index_ = getSpaceCadetKeyIndex(event.key);
     if (pending_map_index_ >= 0) {
-      // A SpaceCadet key was pressed
+      // A SpaceCadet key has just toggled on. First, if we're in no-delay mode,
+      // we need to send the event unchanged (with the primary `Key` value),
+      // bypassing other `onKeyswitchEvent()` handlers.
+      if (mode_ == Mode::NO_DELAY)
+        Runtime.handleKeyEvent(event);
+      // Queue the press event and abort; this press event will be resolved
+      // later.
       event_queue_.append(event);
       return EventHandlerResult::ABORT;
     }
@@ -211,6 +200,11 @@ void SpaceCadet::flushQueue() {
 void SpaceCadet::flushEvent(bool is_tap) {
   KeyEvent event = event_queue_.event(0);
   if (is_tap && pending_map_index_ >= 0) {
+    // If we're in no-delay mode, we should first send the release of the
+    // modifier key as a courtesy before sending the tap event.
+    if (mode_ == Mode::NO_DELAY) {
+      Runtime.handleKeyEvent(KeyEvent(event.addr, WAS_PRESSED));
+    }
     event.key = map[pending_map_index_].output;
   }
   event_queue_.shift();
diff --git a/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.h b/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.h
index 971bb540..3365d755 100644
--- a/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.h
+++ b/plugins/Kaleidoscope-SpaceCadet/src/kaleidoscope/plugin/SpaceCadet.h
@@ -60,9 +60,18 @@ class SpaceCadet : public kaleidoscope::Plugin {
   SpaceCadet(void);
 
   // Methods
-  static void enable(void);
-  static void disable(void);
-  static bool active(void);
+  static void enable() {
+    mode_ = Mode::ON;
+  }
+  static void disable() {
+    mode_ = Mode::OFF;
+  }
+  static void enableWithoutDelay() {
+    mode_ = Mode::NO_DELAY;
+  }
+  static bool active() {
+    return (mode_ == Mode::ON || mode_ == Mode::NO_DELAY);
+  }
 
   // Publically accessible variables
   static uint16_t time_out;  //  The global timeout in milliseconds
@@ -73,7 +82,12 @@ class SpaceCadet : public kaleidoscope::Plugin {
   EventHandlerResult afterEachCycle();
 
  private:
-  static bool disabled;
+  enum Mode : uint8_t {
+    ON,
+    OFF,
+    NO_DELAY,
+  };
+  static uint8_t mode_;
 
   static KeyEventTracker event_tracker_;
 
diff --git a/tests/plugins/SpaceCadet/no-delay/no-delay.ino b/tests/plugins/SpaceCadet/no-delay/no-delay.ino
new file mode 100644
index 00000000..7881a202
--- /dev/null
+++ b/tests/plugins/SpaceCadet/no-delay/no-delay.ino
@@ -0,0 +1,68 @@
+/* -*- mode: c++ -*-
+ * Copyright (C) 2021  Keyboard.io, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <Kaleidoscope.h>
+#include <Kaleidoscope-SpaceCadet.h>
+
+// *INDENT-OFF*
+KEYMAPS(
+    [0] = KEYMAP_STACKED
+    (
+        Key_LeftShift, Key_RightShift, ___, ___, ___, ___, ___,
+        Key_A, Key_B, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___,
+        ___,
+
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___, ___, ___, ___,
+        ___, ___, ___, ___,
+        ___
+    ),
+)
+// *INDENT-ON*
+
+KALEIDOSCOPE_INIT_PLUGINS(SpaceCadet);
+
+void setup() {
+  Kaleidoscope.setup();
+
+  //Set the SpaceCadet map
+  //Setting is {KeyThatWasPressed, AlternativeKeyToSend, TimeoutInMS}
+  //Note: must end with the SPACECADET_MAP_END delimiter
+  static kaleidoscope::plugin::SpaceCadet::KeyBinding spacecadetmap[] = {
+    {Key_LeftShift, Key_X, 10},
+    {Key_RightShift, Key_Y, 0},
+    {Key_LeftGui, Key_LeftCurlyBracket, 10},
+    {Key_RightAlt, Key_RightCurlyBracket, 10},
+    {Key_LeftAlt, Key_RightCurlyBracket, 10},
+    {Key_LeftControl, Key_LeftBracket, 10},
+    {Key_RightControl, Key_RightBracket, 10},
+    SPACECADET_MAP_END
+  };
+  //Set the map.
+  SpaceCadet.map = spacecadetmap;
+  SpaceCadet.time_out = 20;
+
+  SpaceCadet.enableWithoutDelay();
+}
+
+void loop() {
+  Kaleidoscope.loop();
+}
diff --git a/tests/plugins/SpaceCadet/no-delay/sketch.json b/tests/plugins/SpaceCadet/no-delay/sketch.json
new file mode 100644
index 00000000..8cc86922
--- /dev/null
+++ b/tests/plugins/SpaceCadet/no-delay/sketch.json
@@ -0,0 +1,6 @@
+{
+  "cpu": {
+    "fqbn": "keyboardio:virtual:model01",
+    "port": ""
+  }
+}
diff --git a/tests/plugins/SpaceCadet/no-delay/test.ktest b/tests/plugins/SpaceCadet/no-delay/test.ktest
new file mode 100644
index 00000000..ba35c59a
--- /dev/null
+++ b/tests/plugins/SpaceCadet/no-delay/test.ktest
@@ -0,0 +1,141 @@
+VERSION 1
+
+KEYSWITCH LSHIFT    0 0
+KEYSWITCH RSHIFT    0 1
+KEYSWITCH A         1 0
+KEYSWITCH B         1 1
+
+# ==============================================================================
+NAME SpaceCadet tap
+
+RUN 4 ms
+PRESS LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift # Report should contain `shift` (0xE1)
+
+RUN 4 ms
+RELEASE LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+EXPECT keyboard-report Key_X # Report should contain `X` (0x1B)
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms
+
+# ==============================================================================
+NAME SpaceCadet hold
+
+RUN 4 ms
+PRESS LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift # Report should contain `shift` (0xE1)
+
+RUN 10 ms # timeout = 10 ms (for this key)
+RELEASE LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms
+
+# ==============================================================================
+NAME SpaceCadet hold with global timeout
+
+RUN 4 ms
+PRESS RSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_RightShift # Report should contain `shift` (0xE5)
+
+RUN 20 ms # timeout = 20 ms
+RELEASE RSHIFT
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms
+
+# ==============================================================================
+NAME SpaceCadet interrupt
+
+RUN 4 ms
+PRESS LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift # Report should contain `shift` (0xE1)
+
+RUN 4 ms
+PRESS A
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift Key_A # Report should add `A` (0x04, 0xE1)
+
+RUN 4 ms
+RELEASE LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_A # Report should contain only `A` (0x04)
+
+RUN 4 ms
+RELEASE A
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms
+
+# ==============================================================================
+NAME SpaceCadet interrupt SpaceCadet with tap
+
+RUN 4 ms
+PRESS LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift # Report should contain `shift` (0xE1)
+
+RUN 4 ms
+PRESS RSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift Key_RightShift # Report should add `shift` (0xE5)
+
+RUN 4 ms
+RELEASE RSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift # Report should contain `shift` (0xE1)
+EXPECT keyboard-report Key_LeftShift Key_Y # Report should add `Y` (0x1C)
+EXPECT keyboard-report Key_LeftShift # Report should contain `shift` (0xE1)
+
+RUN 4 ms
+RELEASE LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms
+
+# ==============================================================================
+NAME SpaceCadet interrupt SpaceCadet with hold
+
+# First, press left shift. It takes effect immediately, because SpaceCadet is in
+# "no-delay" mode.
+RUN 4 ms
+PRESS LSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift # report: { e1 }
+
+# Before left shift times out (timeout=10ms), press right shift, which also
+# takes effect without delay.
+RUN 4 ms
+PRESS RSHIFT
+RUN 1 cycle
+EXPECT keyboard-report Key_LeftShift Key_RightShift # report: { e1 e5 }
+
+# Next, release left shift after it times out (so it's not a "tap"), but before
+# the right shift times out. This does not generate a report, because the right
+# shift might still become a "tap" if it's released soon enough.
+RUN 10 ms
+RELEASE LSHIFT
+
+# Next, the right shift times out, resolving to its modifier state. This allows
+# the left shift to be released, because the right shift can't be a "tap".
+RUN 10 ms
+EXPECT keyboard-report Key_RightShift # Report should contain `shift` (0xE5)
+
+# Last, release the right shift as normal.
+RUN 4 ms
+RELEASE RSHIFT
+RUN 1 cycle
+EXPECT keyboard-report empty # Report should be empty
+
+RUN 5 ms