To be adopted by architects, modelling approaches must provide a means to leverage the software patterns and architectural styles that are relevant to development practice, instead of those proscribed by black-box CASE tools. Architecture-Centric Model-Driven Software Development (AC-MDSD) is a modelling approach that provides architectural control of the generated application. However, AC-MDSD primarily focuses on generating infrastructure code. We apply AC-MDSD to web engineering and contribute a technique to define and generate system behaviour that goes beyond the create/read/update/delete infrastructure functionality. We use UML profiles augmented with OCL to specify the behaviour. We provide an example to illustrate the approach and outcomes.