While doing some browser testing this week, [Mark](http://clearleft.com/is/mark-perkins) come across a particularly wicked front-end problem. Something was triggering compatibility mode in Internet Explorer 8 and he couldn’t figure out what it was.
Pattern portfolios are a great way to deliver modular, flexible and responsive design systems. They also offer huge benefits to both clients and technical partners when compared to traditional page-by-page static page template deliverables.
Performance considerations in responsive design should be a holistic part of the shaping of a site, right from the initial UX work. Using the concept of a ‘size budget’ can help avoid making it just a development issue that gets tacked on at the end.