Silicon Valley based computer human interaction consultancy focusing on practical usability testing and interface design. Located in California, USA.

Committed to liberating technology from the technologists and letting people play with it instead. Focus on usability and accessibility of interface design. Located in Australia.

Usability and User Interface Designers. Located in New York, USA.

Specializes in goal-based user interface design and field studies to find out the users' goals. Provides usability assessment, e.g. expert reviews and usability testing. Located in Finland.

Examining the online sales process from the customer's point of view. Located in England.

Offers usability evaluations, user-centered front-ends, software product design, and training. Located in India.

User interface design and usability evaluation consultancy. Located in London, United Kingdom.

User experience consulting. Including articles and news about Web usability. From Denmark.

Experts in user interface design for applications and other web-based products. Located in California, USA.

Internet effectiveness consultancy offers a range of services including web site evaluations and search engine optimization. Located in Ontario, Canada.