The real needs of end users of software technology are often neglected until it is too late. An approach is outlined that puts people before technology, and investigates the real needs of field-based workers in relation to the concept of a computer system for just-in-context, or field-based mobile learning. A scenario based approach is used to elicit real-world requirements, with further data captured through user profiling, task analysis and context definition using experts in relevant domains. Specific scenarios and profiles are analysed and generic requirements proposed as an initial step to encourage user need before unsolicited software design is imposed. KEYWORDS Usability, mLearning, context, field-based, mobile, worker.