One HR and one technical remote Skype session, then 2 full working days on site (usually 10h+ each). All requested skills are tested and evaluated while creating a mock enterprise application, with high attention to implementation and design details. Offer negotiation at the end of the 2nd day. Selection process is rather restrictive, but some lacks in skills are accepted if the general thinking is fine. Quite necessary to quickly recognize and adapt company's standards.
NOTE: best to have own laptop with all the development environment prepared, to avoid time consuming configuration or keyboard layout issues.