diff --git a/wp-admin/admin.php b/wp-admin/admin.php
index ab53b4c5da..12d56c429d 100644
--- a/wp-admin/admin.php
+++ b/wp-admin/admin.php
@@ -17,7 +17,7 @@ nocache_headers();
 
 update_category_cache();
 
-get_currentuserinfo();
+wp_get_current_user();
 
 $posts_per_page = get_settings('posts_per_page');
 $what_to_show = get_settings('what_to_show');
diff --git a/wp-admin/comment.php b/wp-admin/comment.php
index 2a97d91724..e431c3d571 100644
--- a/wp-admin/comment.php
+++ b/wp-admin/comment.php
@@ -26,8 +26,6 @@ case 'editcomment':
 	$editing = true;
 	require_once ('admin-header.php');
 
-	get_currentuserinfo();
-
 	$comment = (int) $_GET['comment'];
 
 	if ( ! $comment = get_comment($comment) )
diff --git a/wp-admin/edit-form-ajax-cat.php b/wp-admin/edit-form-ajax-cat.php
index 06b260aaae..1da142f852 100644
--- a/wp-admin/edit-form-ajax-cat.php
+++ b/wp-admin/edit-form-ajax-cat.php
@@ -3,8 +3,6 @@ require_once('../wp-config.php');
 require_once('admin-functions.php');
 require_once('admin-db.php');
 
-get_currentuserinfo();
-
 if ( !current_user_can('manage_categories') )
 	die('-1');
 
diff --git a/wp-admin/list-manipulation.php b/wp-admin/list-manipulation.php
index 623226aa6c..44563b8079 100644
--- a/wp-admin/list-manipulation.php
+++ b/wp-admin/list-manipulation.php
@@ -3,7 +3,6 @@ require_once('../wp-config.php');
 require_once('admin-functions.php');
 require_once('admin-db.php');
 
-get_currentuserinfo();
 if ( !is_user_logged_in() )
 	die('-1');
 
diff --git a/wp-admin/options.php b/wp-admin/options.php
index 8895bcef43..5e479e45d7 100644
--- a/wp-admin/options.php
+++ b/wp-admin/options.php
@@ -68,8 +68,6 @@ case 'update':
 			if ( get_settings('siteurl') != $old_siteurl || get_settings('home') != $old_home ) {
 				// If home changed, write rewrite rules to new location.
 				$wp_rewrite->flush_rules();
-				// Get currently logged in user and password.
-				get_currentuserinfo();
 				// Clear cookies for old paths.
 				wp_clearcookie();
 				// Set cookies for new paths.
diff --git a/wp-admin/page-new.php b/wp-admin/page-new.php
index 8435c17280..61f77a932b 100644
--- a/wp-admin/page-new.php
+++ b/wp-admin/page-new.php
@@ -13,8 +13,6 @@ require_once('admin-header.php');
 <?php
 if ( current_user_can('edit_pages') ) {
 	$action = 'post';
-	get_currentuserinfo();
-
 	$post = get_default_post_to_edit();
 	$post->post_type = 'page';
 
diff --git a/wp-comments-post.php b/wp-comments-post.php
index e2ccba6af9..0d2ab03445 100644
--- a/wp-comments-post.php
+++ b/wp-comments-post.php
@@ -24,11 +24,11 @@ $comment_author_url   = trim($_POST['url']);
 $comment_content      = trim($_POST['comment']);
 
 // If the user is logged in
-get_currentuserinfo();
-if ( $user_ID ) :
-	$comment_author       = $wpdb->escape($user_identity);
-	$comment_author_email = $wpdb->escape($user_email);
-	$comment_author_url   = $wpdb->escape($user_url);
+$user = wp_get_current_user();
+if ( $user->ID ) :
+	$comment_author       = $wpdb->escape($user->display_name);
+	$comment_author_email = $wpdb->escape($user->user_email);
+	$comment_author_url   = $wpdb->escape($user->user_url);
 else :
 	if ( get_option('comment_registration') )
 		die( __('Sorry, you must be logged in to post a comment.') );
@@ -36,7 +36,7 @@ endif;
 
 $comment_type = '';
 
-if ( get_settings('require_name_email') && !$user_ID ) {
+if ( get_settings('require_name_email') && !$user->ID ) {
 	if ( 6 > strlen($comment_author_email) || '' == $comment_author )
 		die( __('Error: please fill the required fields (name, email).') );
 	elseif ( !is_email($comment_author_email))
@@ -50,7 +50,7 @@ $commentdata = compact('comment_post_ID', 'comment_author', 'comment_author_emai
 
 wp_new_comment( $commentdata );
 
-if ( !$user_ID ) :
+if ( !$user->ID ) :
 	setcookie('comment_author_' . COOKIEHASH, stripslashes($comment_author), time() + 30000000, COOKIEPATH, COOKIE_DOMAIN);
 	setcookie('comment_author_email_' . COOKIEHASH, stripslashes($comment_author_email), time() + 30000000, COOKIEPATH, COOKIE_DOMAIN);
 	setcookie('comment_author_url_' . COOKIEHASH, stripslashes(clean_url($comment_author_url)), time() + 30000000, COOKIEPATH, COOKIE_DOMAIN);
diff --git a/wp-includes/capabilities.php b/wp-includes/capabilities.php
index e72f0d1184..3810aa72a2 100644
--- a/wp-includes/capabilities.php
+++ b/wp-includes/capabilities.php
@@ -395,7 +395,7 @@ function map_meta_cap($cap, $user_id) {
 
 // Capability checking wrapper around the global $current_user object.
 function current_user_can($capability) {
-	global $current_user;
+	$current_user = wp_get_current_user();
 
 	$args = array_slice(func_get_args(), 1);
 	$args = array_merge(array($capability), $args);
diff --git a/wp-includes/classes.php b/wp-includes/classes.php
index abb0f3d8e7..9e22a99e57 100644
--- a/wp-includes/classes.php
+++ b/wp-includes/classes.php
@@ -1587,7 +1587,6 @@ class WP {
 	}
 
 	function send_headers() {
-		global $current_user;
 		@header('X-Pingback: '. get_bloginfo('pingback_url'));
 		if ( is_user_logged_in() )
 			nocache_headers();
@@ -1664,7 +1663,7 @@ class WP {
 	}
 
 	function init() {
-		get_currentuserinfo();
+		wp_get_current_user();
 	}
 
 	function query_posts() {
diff --git a/wp-includes/comment-functions.php b/wp-includes/comment-functions.php
index a61610aea5..4a5f676685 100644
--- a/wp-includes/comment-functions.php
+++ b/wp-includes/comment-functions.php
@@ -18,8 +18,6 @@ function comments_template( $file = '/comments.php' ) {
 		$comments = $wpdb->get_results("SELECT * FROM $wpdb->comments WHERE comment_post_ID = '$post->ID' AND ( comment_approved = '1' OR ( comment_author = '$author_db' AND comment_author_email = '$email_db' AND comment_approved = '0' ) ) ORDER BY comment_date");
 	}
 
-	get_currentuserinfo();
-
 	define('COMMENTS_TEMPLATE', true);
 	$include = apply_filters('comments_template', TEMPLATEPATH . $file );
 	if ( file_exists( $include ) )
diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 0c3cda29cb..c0df33f40c 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -303,10 +303,10 @@ function get_option($option) {
 }
 
 function get_user_option( $option, $user = 0 ) {
-	global $wpdb, $current_user;
+	global $wpdb;
 
 	if ( empty($user) )
-		$user = $current_user;
+		$user = wp_get_current_user();
 	else
 		$user = get_userdata($user);
 
@@ -1176,6 +1176,28 @@ function setup_postdata($post) {
 	return true;
 }
 
+// Setup global user vars.  Used by set_current_user() for back compat.
+function setup_userdata($user_id = '') {
+	global $user_login, $userdata, $user_level, $user_ID, $user_email, $user_url, $user_pass_md5, $user_identity;
+
+	if ( '' == $user_id )
+		$user = wp_get_current_user();
+	else 
+		$user = new WP_User($user_id);
+
+	if ( 0 == $user->ID )
+		return;
+
+	$userdata = $user->data;
+	$user_login	= $user->user_login;
+	$user_level	= $user->user_level;
+	$user_ID	= $user->ID;
+	$user_email	= $user->user_email;
+	$user_url	= $user->user_url;
+	$user_pass_md5	= md5($user->user_pass);
+	$user_identity	= $user->display_name;
+}
+
 function is_new_day() {
 	global $day, $previousday;
 	if ( $day != $previousday ) {
diff --git a/wp-includes/kses.php b/wp-includes/kses.php
index a0bdf2c8da..97bed209a5 100644
--- a/wp-includes/kses.php
+++ b/wp-includes/kses.php
@@ -528,16 +528,11 @@ function kses_init_filters() {
 }
 
 function kses_init() {
-	global $current_user;
-
 	remove_filter('pre_comment_author', 'wp_filter_kses');
 	remove_filter('pre_comment_content', 'wp_filter_kses');
 	remove_filter('content_save_pre', 'wp_filter_post_kses');
 	remove_filter('title_save_pre', 'wp_filter_kses');
 
-	if (! defined('XMLRPC_REQUEST') )
-		get_currentuserinfo();
-
 	if (current_user_can('unfiltered_html') == false)
 		kses_init_filters();
 }
diff --git a/wp-includes/pluggable-functions.php b/wp-includes/pluggable-functions.php
index 6856c1c7e6..cc1030ae9e 100644
--- a/wp-includes/pluggable-functions.php
+++ b/wp-includes/pluggable-functions.php
@@ -5,21 +5,20 @@
 
 if ( !function_exists('set_current_user') ) :
 function set_current_user($id, $name = '') {
-	global $user_login, $userdata, $user_level, $user_ID, $user_email, $user_url, $user_pass_md5, $user_identity, $current_user;
+	return wp_set_current_user($id, $name);
+}
+endif;
 
-	$current_user	= '';
+if ( !function_exists('wp_set_current_user') ) :
+function wp_set_current_user($id, $name = '') {
+	global $current_user;
 
-	$current_user	= new WP_User($id, $name);
+	if ( isset($current_user) && ($id == $current_user->ID) )
+		return $current_user;
 
-	$userdata	= get_userdatabylogin($user_login);
+	$current_user = new WP_User($id, $name);
 
-	$user_login	= $userdata->user_login;
-	$user_level	= $userdata->user_level;
-	$user_ID	= $userdata->ID;
-	$user_email	= $userdata->user_email;
-	$user_url	= $userdata->user_url;
-	$user_pass_md5	= md5($userdata->user_pass);
-	$user_identity	= $userdata->display_name;
+	setup_userdata($current_user->ID);
 
 	do_action('set_current_user');
 
@@ -27,30 +26,34 @@ function set_current_user($id, $name = '') {
 }
 endif;
 
+if ( !function_exists('current_user') ) :
+function wp_get_current_user() {
+	global $current_user;
+
+	get_currentuserinfo();
+
+	return $current_user;
+}
+endif;
 
 if ( !function_exists('get_currentuserinfo') ) :
 function get_currentuserinfo() {
-	global $user_login, $userdata, $user_level, $user_ID, $user_email, $user_url, $user_pass_md5, $user_identity, $current_user;
+	global $current_user;
 
 	if ( defined('XMLRPC_REQUEST') && XMLRPC_REQUEST )
 		return false;
 
+	if ( ! empty($current_user) )
+		return;
+
 	if ( empty($_COOKIE[USER_COOKIE]) || empty($_COOKIE[PASS_COOKIE]) || 
 		!wp_login($_COOKIE[USER_COOKIE], $_COOKIE[PASS_COOKIE], true) ) {
-		$current_user = new WP_User(0);
+		wp_set_current_user(0);
 		return false;
 	}
-	$user_login  = $_COOKIE[USER_COOKIE];
-	$userdata    = get_userdatabylogin($user_login);
-	$user_level  = $userdata->user_level;
-	$user_ID     = $userdata->ID;
-	$user_email  = $userdata->user_email;
-	$user_url    = $userdata->user_url;
-	$user_pass_md5 = md5($userdata->user_pass);
-	$user_identity = $userdata->display_name;
 
-	if ( empty($current_user) )
-		$current_user = new WP_User($user_ID);
+	$user_login = $_COOKIE[USER_COOKIE];
+	wp_set_current_user(0, $user_login);
 }
 endif;
 
@@ -201,10 +204,11 @@ endif;
 
 if ( !function_exists('is_user_logged_in') ) :
 function is_user_logged_in() {
-	global $current_user;
+	$user = wp_get_current_user();
 
-	if ( $current_user->id == 0 )
+	if ( $user->id == 0 )
 		return false;
+
 	return true;
 }
 endif;
diff --git a/wp-includes/registration-functions.php b/wp-includes/registration-functions.php
index 26f0a80402..4805f45dac 100644
--- a/wp-includes/registration-functions.php
+++ b/wp-includes/registration-functions.php
@@ -101,7 +101,7 @@ function wp_insert_user($userdata) {
 }
 
 function wp_update_user($userdata) {
-	global $wpdb, $current_user;
+	global $wpdb;
 
 	$ID = (int) $userdata['ID'];
 
@@ -122,6 +122,7 @@ function wp_update_user($userdata) {
 	$user_id = wp_insert_user($userdata);
 
 	// Update the cookies if the password changed.
+	$current_user = wp_get_current_user();
 	if( $current_user->id == $ID ) {
 		if ( isset($plaintext_pass) ) {
 			wp_clearcookie();
diff --git a/wp-includes/template-functions-general.php b/wp-includes/template-functions-general.php
index 1efe9092e5..4a0fd89c12 100644
--- a/wp-includes/template-functions-general.php
+++ b/wp-includes/template-functions-general.php
@@ -27,10 +27,7 @@ function get_sidebar() {
 
 
 function wp_loginout() {
-	global $user_ID;
-	get_currentuserinfo();
-
-	if ('' == $user_ID)
+	if ( ! is_user_logged_in() )
 		$link = '<a href="' . get_settings('siteurl') . '/wp-login.php">' . __('Login') . '</a>';
 	else
 		$link = '<a href="' . get_settings('siteurl') . '/wp-login.php?action=logout">' . __('Logout') . '</a>';
@@ -40,16 +37,15 @@ function wp_loginout() {
 
 
 function wp_register( $before = '<li>', $after = '</li>' ) {
-	global $user_ID;
 
-	get_currentuserinfo();
-
-	if ( '' == $user_ID && get_settings('users_can_register') )
-		$link = $before . '<a href="' . get_settings('siteurl') . '/wp-register.php">' . __('Register') . '</a>' . $after;
-	elseif ( '' == $user_ID && !get_settings('users_can_register') )
-		$link = '';
-	else
+	if ( ! is_user_logged_in() ) {
+		if ( get_settings('users_can_register') )
+			$link = $before . '<a href="' . get_settings('siteurl') . '/wp-register.php">' . __('Register') . '</a>' . $after;
+		else
+			$link = '';
+	} else {
 		$link = $before . '<a href="' . get_settings('siteurl') . '/wp-admin/">' . __('Site Admin') . '</a>' . $after;
+	}
 
 	echo apply_filters('register', $link);
 }