Software has gained an essential role in our daily life in the last decades. This condition demands high quality software. To produce high quality software many practitioners and researchers put more attention on the software development process. Large investments are poured to improve the software development process. Software Process Improvement (SPI) is a research area which is aimed to address the assessment and improvement issues in the software development process. One of the most important aspects in software process improvement is to measure the results gained from the embarked process change. Without measuring the results, it is hard to tell whether the goals have been achieved or not. However, measurement for software process improvement is not a trivial task. Furthermore, there is no common systematic methodology that can be used to help measuring the performance of software process improvement initiatives. This thesis is intended to provide basic key concepts for the effective measurement and evaluation of the outcome of software process improvement. A major part of this thesis presents the systematic review in evaluating the outcome of software process improvement. The systematic review is aimed at the identification of the major issues in software process improvement evaluation and to gather the requirements for a software process improvement measurement and evaluation framework. Based on the results of the systematic review, a measurement and evaluation model is formulated. The objective of the model is to provide the groundwork for a software process improvement measurement and evaluation framework. The model is deemed to be applicable in a broad spectrum of scenarios by providing concepts that are independent from specific SPI initiatives.