Many types of e-services must conform to legally binding requirements, which can be specified in the law or in regulations or in binding agreements. These requirements can be of very different types, ranging from contractual obligations, to organization structure, to privacy obligations. They must be identified and extracted from legal or legally binding texts to become implementation requirements. From the software engineering point of view this is a complex endeavor, in part because the source texts are based on implicit ontologies that should be well understood although in reality they are fuzzy and unstable. The implementation of the requirements and of its underlying ontologies must be shown (and possibly certified) to be conformant with the requirements, by means such as formal verification or testing. This talk will discuss some of the research challenges in this area, together with some possible solutions.