It depends on where you're applying, and the source of your master's degree. For example:
- the Federal Government hires on a points scale, so it is necessary to have an evaluation that states your degree is equivalent to a Canadian one. Without that, they won't give you points, as it reduces the impartiality of the process.
- if you're applying to a company, and your degree is in accounting, having the evaluation is not a formal requirement, but it certainly helps. The company can do whatever they want, and if you can demonstrate that you're a master of your subject, they probably won't care that much about the evaluation. However, for a technical field, having the evaluation is probably a good idea, particularly since technical fields are more likely to be regulated (which means that to be licensed you will have to do this anyway).
- if your master's is in European history, there's no point. A degree in European history from Toronto isn't equivalent to a degree in European history from Guelph, and neither of them will produce a student with an internationally accepted set of qualities (unlike accounting or nursing). In this area, your department, your unique knowledge, and your personal skills are more important than the technical details of your degree. Of course, if you come from some country where a master's degree has a completely different name, then it is probably a good idea -- but as long as you have a transcript in English, that should be enough.
- what will sometimes be as useful than an evaluation is proof that you went to a good, recognized, accredited school. If you're from India and you went to the best university in Kerala, find a way to demonstrate that. The fact that you were admitted to and succeeded in a competitive academic environment is important, in Canada that is the difference between Toronto/Waterloo and a whole bunch of sub-regional colleges.
