Remember that an essay is simply a discussion / argument on paper.
Don't make the mistake of writing all the information you know regarding a particular topic.
It would be useful at the beginning of each paragraph if you explicitly outlined the theme being discussed (.e.g. Psychology is a science so you must support your ideas with evidence (not your own personal opinion).
If you are discussing a theory or research study make sure you cite the source of the information.
It is very important to elaborate on your evaluation.
Don't just write a shopping list of brief (one or two sentence) evaluation points.
Furthermore, the levels of dependency of depressed clients mean that transference is more likely to develop.
It is often best to write your introduction when you have finished the main body of the essay, so that you have a good understanding to the topic area.
Rather than hunting for weaknesses in every study; only highlight limitations which make you doubt the conclusions that the authors have drawn – e.g.
where an alternative explanation might be equally likely because something hasn’t been adequately controlled.