This book reports on the research carried out to identify software architectural quality attributes with a view to ensuring that existing software systems follow a specific architecture for the quality to be determined exactly at all times. Qualitative and quantitative research approaches were used for the development and evaluation of an improved model. The model, Software Architecture Scenario-Based Performance Quality Model (SASPQuM) was developed in Unified Modelling Language using AgroUML Computer Aided Systems Engineering tool. The developed model was categorised into three: stimuli, architectural decisions, and responses. These were mathematically represented and simulated using MATLAB. The validity of the model was tested on an existing software architecture - Made in Nigeria Primary Healthcare Information System software (MINPHIS) and the Architecture Trade-off Analysis Method (ATAM) was used to evaluate the architecture. The research related software architecture to software quality and attached value to quality attributes since they manifest themselves as part of the execution model of the software running on a computer.