BACKGROUND:Many surgeons now incorporate Acellular Dermal Matrix (ADM) into expander-based breast reconstruction. ADM is safe, provides full expander coverage, eliminates the need for additional muscular dissection and has improved aesthetic outcomes. However, its use increases surgical costs. Whether this cost is offset by decreased operative times or a reduced number of revision procedures is unknown. METHODS:We have developed a new technique that minimises the amount of ADM required in many patients. The 'partial sling' approach has been used for 145 consecutive patients (197 breasts) by a single surgeon from 2007 to 2010. After mastectomy, any portion of the pectoralis major insertion at, or <1 cm from, the planned inframmary fold is left intact and becomes the inferior margin of the expander pocket. The minimal size of ADM required is then determined by measuring from the pectoralis to the lateral breast margin. In this study, we exclusively used AlloDerm. Preoperative breast measurements, intra-operative fill volume, time to exchange procedure, number of expansion procedures and complications were recorded for all patients. RESULTS:Patients were grouped according to the surface area (cm(2)) of ADM required. Good aesthetic outcomes were obtained in all groups. Two groups had a significant difference in intra-operative fill volumes but this did not correlate to an increase in the number of expansion procedures required. Of 197 reconstructed breasts less than 64 cm(2) of ADM was used for 40 breasts (20%). CONCLUSIONS:The partial AlloDerm sling can minimise the costs associated with ADM use in breast reconstruction for many patients without increasing complications or altering aesthetic outcomes.