Abstract: Product line software engineering should include an up-front and ongoing investment in a reusable architecture. In some cases, only architecture can be reused in the first phases of utilising the product line concept in the development of evolutionary embedded software products. Identification, selection, documentation and validation of general architectural patterns and their product line, organisation or domain specific variants allow designers to adopt approved patterns as a starting point. This paper discusses how to apply design patterns to introduction problems of product lines, including various and evolutionary design techniques of embedded software. The patterns are a precondition for the development of frameworks for designing and reusing architectures of the sub-domains that promise the highest benefits. The classification of core architectural assets helps to achieve a balance between discipline product line architecture and creativity forced by future needs that are not fully predictable.