Testing People at Work is an authoritative, practical text on selection and assessment. It explains psychometric testing in occupational settings and also covers other methods of selection such as assessment centres and e-selection. The book systematically covers all the topics required for the BPS Certificates of Competence in Testing Levels A and B.
Good summary textbook on best practice in recruitment. Comprehensively covers all topics. A bit short on very psychological-oriented content if that's what you're looking for, but very easy to pick up and read if you're a relative novice / looking for something practitioner friendly. Would recommend this for practical projects and assignments.