diff --git a/README.md b/README.md
index 9b81e64..a570db6 100644
--- a/README.md
+++ b/README.md
@@ -50,32 +50,33 @@ Or, [Dispatch](https://github.com/tpope/vim-dispatch) and
 let g:rspec_command = "compiler rspec | set makeprg=zeus | Make rspec {spec}"
 ```
 
-### Custom runners
+### MacVim command runners
 
-Overwrite the `g:rspec_runner` variable to set a custom launch script. At the
-moment there are two MacVim-specific runners, i.e. `os_x_terminal` and
-`os_x_iterm`. The default is `os_x_terminal`, but you can set this to anything
-you want, provided you include the appropriate script inside the plugin's
-`bin/` directory.
+If you are running your specs from MacVim,
+you must set `g:rspec_runner` or `g:rspec_command`, or both.
 
-#### iTerm instead of Terminal
-
-If you use iTerm, you can set `g:rspec_runner` to use the included iterm
-launching script. This will run the specs in the last session of the current
-terminal.
+The `g:rspec_runner` variable specifies which launch script will be used:
 
 ```vim
 let g:rspec_runner = "os_x_iterm"
 ```
 
-If you use the iTerm2 nightlies, the `os_x_iterm` runner will not work
-(due to AppleScript incompatibilities between the old and new versions of iTerm2).
+At the moment the following MacVim-specific runners are supported:
 
-Instead use the `os_x_iterm2` runner, configure it like so:
+* `os_x_terminal` for OSX Terminal.app
+* `os_x_iterm` for iTerm2 stable release
+  * If you use the iTerm2 nightlies,
+  this runner will not work due to AppleScript incompatibilities
+  between the old and new versions of iTerm2
+* `os_x_iterm2` for iTerm2 nightly builds
 
-```vim
-let g:rspec_runner = "os_x_iterm2"
-```
+If `g:rspec_runner` isn't set,
+the `g:rspec_command` will be executed from MacVim without a runner.
+This enables commands like `Dispatch rspec {spec}` to work in GUI mode.
+
+You can set `g:rspec_runner` to anything you want,
+provided you include the appropriate script
+inside the plugin's `bin/` directory.
 
 ## Running tests
 
diff --git a/plugin/rspec.vim b/plugin/rspec.vim
index 2be9ebc..9762979 100644
--- a/plugin/rspec.vim
+++ b/plugin/rspec.vim
@@ -1,11 +1,6 @@
 let s:plugin_path = expand("<sfile>:p:h:h")
-let s:default_command = "rspec {spec}"
 let s:force_gui = 0
 
-if !exists("g:rspec_runner")
-  let g:rspec_runner = "os_x_terminal"
-endif
-
 function! RunAllSpecs()
   let s:last_spec = "spec"
   call s:RunSpecs(s:last_spec)
@@ -51,32 +46,42 @@ function! s:InSpecFile()
 endfunction
 
 function! s:RspecCommand()
-  if s:RspecCommandProvided() && s:IsMacGui()
-    let l:command = s:GuiCommand(g:rspec_command)
-  elseif s:RspecCommandProvided()
+  if s:RspecCommandProvided()
     let l:command = g:rspec_command
-  elseif s:IsMacGui()
-    let l:command = s:GuiCommand(s:default_command)
   else
-    let l:command = s:DefaultTerminalCommand()
+    let l:command = s:DefaultCommand()
   endif
 
-  return l:command
+  if s:IsMacGui() && s:RspecRunnerProvided()
+    return s:RunnerCommand(l:command)
+  else
+    return l:command
+  endif
 endfunction
 
 function! s:RspecCommandProvided()
   return exists("g:rspec_command")
 endfunction
 
-function! s:DefaultTerminalCommand()
-  return "!" . s:ClearCommand() . " && echo " . s:default_command . " && " . s:default_command
+function! s:RspecRunnerProvided()
+  return exists("g:rspec_runner")
+endfunction
+
+function! s:DefaultCommand()
+  let l:default_command = "rspec {spec}"
+
+  if s:IsMacGui()
+    return l:default_command
+  else
+    return "!" . s:ClearCommand() . " && echo " . l:default_command . " && " . l:default_command
+  endif
 endfunction
 
 function! s:CurrentFilePath()
   return @%
 endfunction
 
-function! s:GuiCommand(command)
+function! s:RunnerCommand(command)
   return "silent ! '" . s:plugin_path . "/bin/" . g:rspec_runner . "' '" . a:command . "'"
 endfunction
 
diff --git a/t/rspec_test.vim b/t/rspec_test.vim
index 50d0e18..90b0333 100644
--- a/t/rspec_test.vim
+++ b/t/rspec_test.vim
@@ -13,16 +13,21 @@ describe "RunSpecs"
     end
 
     context "when in GUI"
-      context "when g:rspec_runner is defined"
+      before
+        call Set("s:force_gui", 1)
+      end
+
+      after
+        call Set("s:force_gui", 0)
+      end
+
+      context "when rspec_runner is defined"
         before
-          call Set("s:force_gui", 1)
-          let s:original_runner = g:rspec_runner
           let g:rspec_runner = "iterm"
         end
 
         after
-          let g:rspec_runner = s:original_runner
-          call Set("s:force_gui", 0)
+          unlet g:rspec_runner
         end
 
         it "sets the command with provided runner"
@@ -35,20 +40,15 @@ describe "RunSpecs"
       end
 
       context "when rspec_runner is not defined"
-        before
-          call Set("s:force_gui", 1)
-        end
-
-        after
-          call Set("s:force_gui", 0)
-        end
-
-        it "sets the command with default runner"
-          let expected = "^silent ! '\.\*/bin/os_x_terminal' 'rspec " . s:filename . "'$"
-
-          call Call("s:RunSpecs", s:filename)
-
-          Expect Ref("s:rspec_command") =~ expected
+        it "sets the default command"
+          let expected = "rspec " . s:filename
+
+          try
+            call Call("s:RunSpecs", s:filename)
+          catch
+          finally
+            Expect Ref("s:rspec_command") =~ expected
+          endtry
         end
       end
     end
@@ -83,11 +83,30 @@ describe "RunSpecs"
         call Set("s:force_gui", 0)
       end
 
-      it "sets the provided GUI command"
-        let expected = "^silent ! '\.\*/bin/os_x_terminal' '!Dispatch rspec " . s:filename . "'$"
-        call Call("s:RunSpecs", s:filename)
+      context "and rspec_runner is defined"
+        before
+          let g:rspec_runner = "fake_runner"
+        end
+
+        after
+          unlet g:rspec_runner
+        end
+
+        it "sets the provided GUI command"
+          let expected = "^silent ! '\.\*/bin/fake_runner' '!Dispatch rspec " . s:filename . "'$"
+          call Call("s:RunSpecs", s:filename)
 
-        Expect Ref("s:rspec_command") =~ expected
+          Expect Ref("s:rspec_command") =~ expected
+        end
+      end
+
+      context "and rspec_runner is not defined"
+        it "sets the provided rspec command"
+          let expected = "Dispatch rspec " . s:filename
+          call Call("s:RunSpecs", s:filename)
+
+          Expect Ref("s:rspec_command") =~ expected
+        end
       end
     end
   end