GSP also features tags to help you manage linking to controllers and actions. The link tag allows you to specify controller and action name pairing and it will automatically work out the link based on the URL Mappings, even if you change them! Some examples of the link can be seen below:

<g:link action="show" id="1">Book 1</g:link>
<g:link action="show" id="${currentBook.id}">${currentBook.name}</g:link>
<g:link controller="book">Book Home</g:link>
<g:link controller="book" action="list">Book List</g:link>
<g:link url="[action:'list',controller:'book']">Book List</g:link>
<g:link action="list" params="[sort:'title',order:'asc',author:currentBook.author]">
     Book List
</g:link>