Almost everybody in the software engineering world has read about or has heard of the importance and benefits of the mature software process. This master thesis aims to answer the question why despite all the efforts; software organizations still have difficulties to achieve the mature and effective software process. The results of the literature survey and a case study performed at a real software company have shown that there is a set of factors that may cause process inefficiency in the software companies. These factors are connected with the soft aspects of the software process such as motivation of the software engineers, process understanding and the process training. / Vad är orsakerna till att programvaruföretagen har svårt att uppnå en mogen och effektiv utvecklingsprocess? Resultatet efter en fallstudie och en literaturundersökning visar att det finns ett antal faktorer som påverkar effektiviteten på processen. / Nina Dzamashvili Övre Brunnsvägen 46, SE-372 36 RONNEBY Sweden E-mail: nina.dzamashvili@bth.se