Software has become an integral part of telecommunication systems over the last 30 years. The relative cost for software in the systems has increased continuously over these years. This increase has meant that there has been a need to also focus on evaluation and prediction of different software qualities of the systems. This paper presents three studies evaluating software qualities in different ways. The firsts study focuses on performance and touches upon reliability. The reliability aspect is discussed in more detail in the second case study. Finally, the third study presents methods to estimate the fault content from software inspections. These studies are presented as representative examples of the work that resulted in that the author of this paper received the Telenor Nordic Research Award in 2004. Some ongoing research on engineering software qualities is also briefly presented.