Wrap-around shielded writers combining both trailing shield and side shield have been studied both by modeling and by experiments. WAS design is demonstrated to have superior performance over its predecessor trailing shielded writer in perpendicular magnetic recording systems. While maintaining the down-track performance, the side shield significantly reduces the side fringing field, thus enabling high track densities. In this paper, various aspects of WAS design are investigated. Issues unique to side shielded design such as near and far track erasure are also discussed in detail. An outlook of future PMR writer and recording systems design is presented at the end.