Studies have been conducted in the past on the effect of collaboration on productivity and quality in software development. In this paper we propose a new framework of Tightly Coupled Engineering Team (TCET) process to facilitate collaboration in a team and thereby improve productivity and software quality. We apply this concept in a 21-month software project for development of a test automation software suite for a real-time embedded medical device at Guidant Corporation. We observe that there is quantitative and qualitative evidence to show that the process contributed to increased productivity and software quality, and there is a definite increase in the intra-team training, ownership, and knowledge flow within the team. We also observe that project risk is reduced without harm to schedule contrary to popular perception that such collaboration may lead to redundancies and thus cost and schedule overrun.

Software testing plays an important role during the software developing period. Any saving on software test will significantly reduce the total cost of software. The key point of this paper is to build a software testing process with the cost control management and to make tradeoffs between the software quality and the software cost. Typical software testing model are analysed and compared. A Quality controlled 3-D testing model is introduced. The model combined with software test process, software quality cost and the testing type. The computational formula is defined to calculate software quality cost. A software quality balance law is introduced to balance control and failure cost. By adjusting software testing method and strategy, organization can reach the objective of the best balance between software quality and the software cost. The result shows an optimistic point that will prove the accurate of the model and the law introduced.