This volume contains a well-chosen selection of Aristotle's works. As another reviewer suggests, this book is a welcome middle ground between 'pocket' editions and a full blown Oxford edition.
The translations (though I am by no means a scholar of Greek) seem to be quite proper, and despite the fact that different sections may be translated by different people, there is no apparent unevenness.
Ackrill laments in the introduction that it would have been more proper to leave about 30-40 Greek words (such as 'logos', 'aitia', 'ousia') untranslated, since no single English word does them justice. But that since there are translations by several people involved, that was not possible.
All in all, this would be a very handy book for anyone interested in Aristotle.
For students who desire neither the whole Oxford corpus or who need a more condensed version of the Oxford translation, this edition, edited by the renowned Aristotlean scholar Ackrill, will be pleasantly kept in good company.
I own both books, and oddly find myself picking up this volume rather than the two-volume set, for easy reference. All the essential material is here, and none of the important elements are injudiciously edited. Thus for a single volume, it does double duty -- providing the most current translation of Aristotle, while appropriately editing the most salient parts for the specialist and non-specialist alike.
The book is appropriate for undergraduate and graduate semester courses as a complete enough text for either venue. It also has a nice topical index in the back that refers the reader to many essays written in the scondary literature.