Very easy, they explain the way they work and salary model, then you ask questions related to your interest. No case or anything like that. Seems they pick you on a CV base and references.

First you have a chat with one of the managers, Webstep is a pretty lean company. They show you how Webstep works, their salary structure, clients and such. You then get a change to introduce yourself, talk about what you do, what you want etc. Webstep only hires senior consultants, i.e. 5 years of experience or more , during the meeting your CV is gone through, talk about particular clients but nothing special. After that, you get a call if they feel you are a good fit or not.