Evaluation: Strengths: A main strength of Milgram’s experiment was the amount of control he was able to administer. For example, participants believed they were being randomly assigned to either the teacher or learner, they believed they were actually administering electric shocks, they all used the same apparatus, had the same prods from the same person and so on. A further strength of this study is that it collected both quantitative and qualitative data which it can be argued increases the validity of the study. Quantitative data included the level of shocks administered and qualitative data was provided through interviews and observation.The study can be said to have high experimental validity because the participants genuinely believed the situation was real, Milgram was measuring actual levels of obedience.Weaknesses: The most common criticism of Milgram’s work is concerned with its ethics: Participants were deceived as to the exact nature of the study for which they had volunteered, and by making them believe they were administering real electric shocks to a real participant. However Milgram could not have found results that truly reflected the way people behave in real situations if he had not deceived his participants, all of whom were thoroughly debriefed afterwards. It can also be argued that Milgram did not take adequate measures to protect his participants from the stress and emotional conflict they experienced. Milgram’s defence was that he, and the students and psychiatrists - who had been asked to predict the results of the first experiment - did not expect the results he obtained, and went on to ask whether such criticisms are based as much on the unexpected results as on the procedure itself. It is possible that being involved in the experiment may have had a long-term effect on the participants. Before the experiment they might have considered themselves incapable of inflicting harm on another person unless the circumstances were extreme.