s- research has found that SD is successful for a range of phobias- McGrath et al reported that about 75% of patients respond to SD. even suitable for those with learning difficulties. demonstrates that it is effective and appropriate. less traumatic than other treatments since its a step-by-step approach. L- while Sd might be effective in the therapeutic situation, it may not work in the real world because they've only applied to one type of atmosphere. Also not effective at treating phobias such as eg fear of dark or heights due to it being an underlying evolutionary survival component. Suggests that SD can can only be used to tackle some phobias.