As part of the continuing programme of evaluation of medical equipment sponsored by the UK Health Departments, the evaluation of dialysis and ancillary equipment is being carried out within the University of Sheffield, under the direction of Professor M. M. Black. 'Health Equipment Information' Number 148, published in December 1985, carries full reports on the Cobe Centry 2Rx haemodialysis system with double blood pump module (DBPM), the Lucas Medical 2100 haemodialysis system, and the Permutit Series 8 water softener. It also contains summaries of full reports on the Organon-Teknika Sorbsystem and Cordis-Dow Seratron haemodialysis systems, and the Gordonsal RD500 and Elga Mediro D water softeners, which were published in 'HEI' 136. Readers should note that the Cordis Seratron and Lucas 2100 models are no longer available in the UK. Extracts of the evaluations of the Cobe Centry 2Rx + DBPM and the Permutit Series B models, together with summaries and overall comparisons, are given below. 'HEI' (ISSN 0261-0736) is free to NHS staff and 5.00 pounds/copy to others. Editorial enquiries to DHSS Scientific and Technical Branch, 14 Russell Square, London WC1B 5EP.