Philosophy encyclopedias have some similarities with buses. You can wait a long time without seeing one and then three come at once. The 1967 first edition of this new encyclopedia, edited by Paul Edwards, was the classic reference work. Indeed, many of the articles from that edition remain in the new second edition (the "2nd edition"). There are also around 450 articles on new subjects and 300 new treatments of subjects that had been covered in the first edition. The second edition maintains the large size of the original edition (each page is slightly larger than european A4) and this allows for a larger typeface than in the recent, also excellent, also 10 volume, Routledge encyclopedia Routledge Encyclopedia of Philosophy. With a work of this nature a larger typeface does increase the ease of reading and comprehension. Some have said that the Routledge offering gives a deeper treatment of the subjects it covers but on balance I have not found this so far.

Serious libraries should have both sets. For libraries with budgetary constraints this 2nd edition is the obvious first choice at a cost of about 10% of the Routledge offering. For even more economy there is also the recently arrived online Stanford encyclopedia, and of course Wikipedia.