Trinity Testing

Trinity Testing combines the knowledge and skills of the team to improve the quality of the software, and the testing. It consists of a short session, of around 90 minutes per feature, where the feature owner, the developer and the test engineer work interactively through the software to share knowledge and ideas. In particular, test engineers are able to provide immediate feedback, identify areas of concern, and devise useful testing strategies per feature.

Each person benefits: the tester knows where to focus their testing, the engineer can correct issues identified during the session while the code is fresh rather than waiting for bug reports, and the feature owner gets a better feature :)  Retrospectives are included at the end of each cycle to help improve the process and practices.

A similar concept - called the 'power of three'  is described in Agile Testing, a book by Lisa Crispin and Janet Gregory  see for more information.