There are different categories of work permits such as open work permits and LMIA supported work permits. A common work permit application wherein the employer is not involved is similar to other temporary entry applications. However, some applications can be more complicated. Labour Market Impact Assessment (commonly known as LMIA) is the report, employers need to obtain from ESDC (Employment and Social Development, Canada) before they begin the work permit application process for a foreign worker.

An LMIA based work permit application requires a plethora of documents from the employer as well as the foreign worker. The work permit approval is generally based on the credentials of a foreign worker such as experience and education, English language proficiency, his ties to the country of nationality, and ability to perform the job. The credentials of the company seeking the service of foreign workers also play an important role as the company needs to prove the legitimacy of a business, and the genuine requirement of the foreign worker.