Personal Software Process (PSP) was introduced by Watts Humphrey in CMU/SEI. It is a measured software process aiming at individual software engineers. With the increasing industrial demand for software process improvement, PSP has become a hot topic for software organizations to achieve the goal of total (from macro to micro) quantitative process management. Since higher process capability is recognized as a determinant of better project performance, it is a critical step to assess the personal software process. However, the assessment of PSP capability exhibits Variable Return to Scale (VRS), Multi-Input-Multi-Output (MIMO) and Decision-Making preference problems, which makes existing traditional assessment methods ineffective. In this paper, a novel Personal Software Process Assessment method by synthesizing Data Envelopment Analysis (DEA) and Analytical Hierarchy Process (AHP)—PSPADA is proposed. PSPADA’s hybrid model and fundamental assessment algorithms (incorporating decision-making preferences and estimating return to scale) are introduced. Experimental results show that the proposed PSPADA model would be particularly helpful in assessing the capability of personal software processes under the MIMO and VRS constraint, by incorporating Decision-Making preferences.