diff --git a/init.el b/init.el
index d2bfb7b..24136f9 100644
--- a/init.el
+++ b/init.el
@@ -37,19 +37,19 @@
 
 (defvar prelude-dir (file-name-directory load-file-name)
   "The root dir of the Emacs Prelude distribution.")
-(defvar prelude-modules-dir (concat prelude-dir "prelude/")
+(defvar prelude-modules-dir (expand-file-name  "prelude" prelude-dir)
   "This directory houses all of the built-in Prelude module. You should
 avoid modifying the configuration there.")
-(defvar prelude-personal-dir (concat prelude-dir "personal/")
+(defvar prelude-personal-dir (expand-file-name "personal" prelude-dir)
   "Users of Emacs Prelude are encouraged to keep their personal configuration
 changes in this directory. All Emacs Lisp files there are loaded automatically
 by Prelude.")
-(defvar prelude-vendor-dir (concat prelude-dir "vendor/")
+(defvar prelude-vendor-dir (expand-file-name "vendor" prelude-dir)
   "This directory house Emacs Lisp packages that are not yet available in
 ELPA (or MELPA).")
-(defvar prelude-snippets-dir (concat prelude-dir "snippets/")
+(defvar prelude-snippets-dir (expand-file-name "snippets" prelude-dir)
   "This folder houses addition yasnippet bundles distributed with Prelude.")
-(defvar prelude-savefile-dir (concat prelude-dir "savefile/")
+(defvar prelude-savefile-dir (expand-file-name "savefile" prelude-dir)
   "This folder stores all the automatically generated save/history-files.")
 
 (unless (file-exists-p prelude-savefile-dir)
@@ -72,7 +72,7 @@ ELPA (or MELPA).")
   (require 'prelude-osx))
 
 ;; config changes made through the customize UI will be store here
-(setq custom-file (concat prelude-personal-dir "custom.el"))
+(setq custom-file (expand-file-name "custom.el" prelude-personal-dir))
 
 ;; load the personal settings (this includes `custom-file')
 (when (file-exists-p prelude-personal-dir)
diff --git a/prelude/prelude-core.el b/prelude/prelude-core.el
index 046580b..af153ef 100644
--- a/prelude/prelude-core.el
+++ b/prelude/prelude-core.el
@@ -39,7 +39,7 @@
   "Adds all first level `parent-dir' subdirs to the
 Emacs load path."
   (dolist (f (directory-files parent-dir))
-    (let ((name (concat parent-dir f)))
+    (let ((name (expand-file-name f parent-dir)))
       (when (and (file-directory-p name)
                  (not (equal f ".."))
                  (not (equal f ".")))
diff --git a/prelude/prelude-editor.el b/prelude/prelude-editor.el
index 4c9afdf..e2a25e7 100644
--- a/prelude/prelude-editor.el
+++ b/prelude/prelude-editor.el
@@ -85,7 +85,7 @@
 (setq uniquify-ignore-buffers-re "^\\*") ; don't muck with special buffers
 
 ;; saveplace remembers your location in a file when saving files
-(setq save-place-file (concat prelude-savefile-dir "saveplace"))
+(setq save-place-file (expand-file-name "saveplace" prelude-savefile-dir))
 ;; activate it for all buffers
 (setq-default save-place t)
 (require 'saveplace)
@@ -97,11 +97,11 @@
       ;; save every minute
       savehist-autosave-interval 60
       ;; keep the home clean
-      savehist-file (concat prelude-savefile-dir "savehist"))
+      savehist-file (expand-file-name "savehist" prelude-savefile-dir))
 (savehist-mode t)
 
 ;; save recent files
-(setq recentf-save-file (concat prelude-savefile-dir "recentf")
+(setq recentf-save-file (expand-file-name "recentf" prelude-savefile-dir)
       recentf-max-saved-items 200
       recentf-max-menu-items 15)
 (recentf-mode t)
@@ -172,7 +172,7 @@
       ido-create-new-buffer 'always
       ido-use-filename-at-point 'guess
       ido-max-prospects 10
-      ido-save-directory-list-file (concat prelude-savefile-dir "ido.hist")
+      ido-save-directory-list-file (expand-file-name "ido.hist" prelude-savefile-dir)
       ido-default-file-method 'selected-window)
 
 ;; auto-completion in minibuffer
@@ -200,7 +200,7 @@
 (require 'expand-region)
 
 ;; bookmarks
-(setq bookmark-default-file (concat prelude-savefile-dir "bookmarks")
+(setq bookmark-default-file (expand-file-name "bookmarks" prelude-savefile-dir)
       bookmark-save-flag 1)
 
 ;; load yasnippet
@@ -210,6 +210,7 @@
 
 ;; projectile is a project management mode
 (require 'projectile)
+(setq projectile-cache-file (expand-file-name  "projectile.cache" prelude-savefile-dir))
 (projectile-global-mode t)
 
 (require 'helm-misc)
@@ -287,10 +288,10 @@ indent yanked text (with prefix arg don't indent)."
 (setq reb-re-syntax 'string)
 
 (require 'eshell)
-(setq eshell-directory-name (concat prelude-savefile-dir "/eshell/"))
+(setq eshell-directory-name (expand-file-name "eshell" prelude-savefile-dir))
 
 (setq semanticdb-default-save-directory
-      (concat prelude-savefile-dir "semanticdb"))
+      (expand-file-name "semanticdb" prelude-savefile-dir))
 
 ;; enable Prelude's keybindings
 (prelude-global-mode t)