Two papers by Jan Gutowski have appeared in the February issue of the Journal of High Energy Physics.  The first paper, co-authored with Samuel Beck and George Papadopoulos (Kings College London), entitled Supersymmetry of AdS and flat IIB backgrounds, presents a systematic description of all warped backgrounds and identifies the a priori number of sypersymmetries N preserved by these solutions. The second paper, co-authored with George Papdopoulos, entitled Supersymmetry of AdS and flat backgrounds in M-theory, gives a systematic description of all warped AdS_n and R^{n-1,1} backgrounds of M-theory and identifies the a priori number of supersymmetries that these backgrounds preserve.