The aim of this article is to review the rationale on which modern aphasia test batteries are based. Since the mid-1950s, a starting point chosen because the discipline of speech (language) pathology was created during that period, a corpus of English aphasia tests was identified through searches of electronic databases. The tests were critically evaluated in terms of their theoretical roots and influences. During the past 50 years, the fundamentals of aphasia assessment remained basically unchanged, that is, to identify and gain insight into the nature and the degree of a language disturbance. However, the way in which the assessment has taken place has shifted back and forth from a purely medical approach to a more neurolinguistic or social approach depending on the influence exerted by different scientific fields. Not a single model on which aphasia assessments rely covers the many and multifaceted problems of individuals with aphasia. At several points in time during the rehabilitation process, the clinician and the patient will encounter a crossroad, where it has to be decided which path to follow next and how to evaluate the covered path. Besides application of formal test batteries, observations in different natural settings, evaluations of functional communication and insights into psychosocial coping contribute towards a holistic approach to aphasia.