Doppler Ankle Brachial Pressure Index (ABPI) is the recommended method of arterial screening (RCN, 1998; SIGN, 1998; CREST, 1998) when assessing patient eligibility for compression therapy. However, in this paper, Janice Bianchi details the potential shortcomings of this technique and describes a newer, simpler test using a pulse oximetry Lanarkshire Oximetry Index which has been shown to be a feasible way to assess whether compression can safely be applied (Lucke et al, 1999; Bianchi et al, 2000; Zamiri et al, 2004) in patients with leg ulcers.