The only way to redirect safely with regards to search engine optimization is to use an 301 Redirect.

Why? 301 keeps the value and weight of the referring page. Robots, like Google, love it. If you are going to delete a page, consider redirecting it using a 301 redirect.

As I’m a “linux web dood”, here is the PHP and .htaccess equivalent:

PHP 301 Redirect

<?php
header( “HTTP/1.1 301 Moved Permanently” );
header( “Location: http://www.new-url.com” );
exit;
?>

The above code must be placed before any output is sent to the browser to avoid any header errors.

.htaccess 301 Redirect

Redirect a single web page to a new location.

redirect 301 /index.html http://www.domain.com/index.html
redirect permanent /index.html http://www.domain.com/index.html
redirectpermanent /index.html http://www.domain.com/index.html

Redirect old domain to new domain

Options +FollowSymLinks
RewriteEngine on
RewriteRule (.*) http://www.newdomain.com/$1 [R=301,L]

There you have it.  Simple, but effective.  Keep your page strengths.  Treat each page as individuals!!