This paper proposes the decision-abstraction and issue-decomposition principles specific to the architectural level design, as well as a decision-centric architecture design method based on the principles. The method models software architectures from the perspective of decisions, accomplishing the design process from eliciting the architecturally significant issues to making decisions on the architecture solutions, it also implements the automated synthesis of the candidate architecture solutions and the capture of the design decisions and rationale. This decision-centric method accommodates the characteristics of architectural level, alleviating the complexity of architecture design and the cost of decisions and rationale capture.