The six primary papers in this issue of "Assessment in Education" emphasise a single primary point: the concept of validity is a complex one. Essentially, validity is a collective noun. That is, just as a group of players may be called a team and a group of geese a flock, so too does validity represent a variety of processes and interpretations all centred on a primary meaning. Validity is not alone in the measurement lexicon for signifying a number of processes. Reliability too means several kinds of consistency: across forms, across times, across test halves and among items composing a test, for example. Yet, different validation processes are all intended to meet certain critical factors: that the scores resulting from the measurement can be used appropriately for certain specified uses and that these same scores can be interpreted reasonably and in ways where different qualified professionals generally would agree on the analysis. Geisinger recommends that, in light of Newton and Shaw's three possibilities for deciding what to do with the term "validity," that the profession redouble efforts to to endorse the concept of validity explicated in the "Standards of Educational and Psychological Testing."