The purpose of business-IT alignment is to optimise the relation between business and IT in order to maximise the business value of IT. Successful business-IT alignment can be enabled by business processes and e-processes functioning as adaptive mediators between business and IT systems. Business processes are the ways actors work in enterprises and collaborate in value networks, while e-processes support a flexible flow of information between IT systems and business processes. The overall goal of this thesis is to propose methods for business process and e-process design and evaluation for achieving alignment between enterprise goals and IT systems. The methods are based on model-driven approaches, using enterprise and software models. More precisely, the proposed methods can be used for designing models of business processes supporting the fulfilment of enterprise goals in the setting of a value network; for designing models of generic and reusable business processes that support the fulfilment of enterprise goals; for designing models of e-processes that support a flexible alignment of IT systems with business processes; and for evaluating the extent to which business processes are aligned with enterprise goals and IT systems. The result of the thesis can be used to support business and system designers with practical knowledge on how to align business and IT systems in order to create efficient, high-quality, flexible and innovative organisations. The research presented in this thesis has been carried out following the design science paradigm. This paradigm is characterised by the creation of new and innovative artefacts for solving general problems, and the evaluation of their benefits and drawbacks.