Good software architecture design is crucial in successfully realising an OOA specification with an appropriate OOD model that meets the specification's functional and non-functional requirements. Unfortunately most CASE tools and software architecture design notations do not adequately support software architecture modelling and analysis, nor integration with OOA and D models. We describe SoftArch, an environment which provides flexible software architecture modelling using a concept of successive refinement. SoftArch also provides extensible analysis tools enabling developers to analyse their architecture model properties. This paper overviews the motivation for SoftArch, its modelling and analysis capabilities, and its integration with various analysis, design and implementation tools.