diff --git a/bundles-init/nerdtree.cfg.vim b/bundles-init/nerdtree.cfg.vim
new file mode 100644
index 0000000..0036dcc
--- /dev/null
+++ b/bundles-init/nerdtree.cfg.vim
@@ -0,0 +1,6 @@
+" NERDTree: ' e' = toggle side bar
+nnoremap <Leader>e :NERDTreeToggle<CR>
+
+" Open automatically if there are more than 150 columns and no file was specified
+autocmd VimEnter * if argc() == 0 && &columns > 150 | NERDTree | endif
+
diff --git a/bundles-init/nerdtree.load.vim b/bundles-init/nerdtree.load.vim
new file mode 100644
index 0000000..50c5513
--- /dev/null
+++ b/bundles-init/nerdtree.load.vim
@@ -0,0 +1 @@
+NeoBundle 'scrooloose/nerdtree'
diff --git a/doc/heavim.txt b/doc/heavim.txt
index 2666836..750c19b 100644
--- a/doc/heavim.txt
+++ b/doc/heavim.txt
@@ -41,3 +41,4 @@ local leader key.
    <Leader>pi           CtrlP: directory
 
    <Leader>t            Toggle tagbar
+   <Leader>e            Toggle NERDtree explorer