There are 2 types of work permits: open work permits and employer-specific work permits.

Open Work Permits

An open work permit allows you to work for any employer in Canada (except for an employer who is listed as ineligible on the list of employers who have failed to comply with the conditions or who offers striptease, erotic dance, escort services or erotic massages)

You can only get an open work permit in specific situations:

• are an international student who graduated from a designated learning institution and are eligible for the Post-Graduation Work Permit Program
• are a student who’s no longer able to meet the costs of your studies (destitute student)
• have an employer-specific work permit and are being abused or at risk of being abused in relation to your job in Canada
• applied for permanent residence in Canada
• are a dependent family member of someone who applied for permanent residence
• are the spouse or common-law partner of a skilled worker or international student
• are the spouse or common-law partner of an applicant of the Atlantic Immigration Pilot Program
• are a refugee, refugee claimant, protected person or their family member
• are under an unenforceable removal order
• are a temporary resident permit holder
• are a young worker participating in special programs

If you are not eligible for an open work permit but would like to work in Canada, you may need an Employer-specific work permit.

Employer-specific Work Permit

An employer-specific work permit allows you to work according to the conditions on your work permit, which include:

• the name of the employer you can work for
• how long you can work
• the location where you can work (if applicable)

How do get an employer-specific work permit?

Employers of some types of temporary workers need to get a Labour Market Impact Assessment (LMIA) before the worker applies for a work permit. An LMIA is a document from Employment and Social Development Canada that gives the employer permission to hire a temporary worker.

A positive LMIA will show that there is a need for a foreign worker to fill the job. It will also show that no Canadian worker or permanent resident is available to do the job.

Working in Canada on a post-graduation work permit

If you are working in Canada on a post-graduation work permit, and have a valid job offer, your current employer will need to get an LMIA if:

• you need one to meet the program requirements for the FSWP or the FSTP and
• your job is not exempt.

If a job is exempt, it means your employer does not need an LMIA to support your job offer. If you are invited under the Canadian Experience Class, you don’t need an LMIA to meet the program requirements.

But, a valid job offer supported by an LMIA can get you more points under the Comprehensive Ranking System. This can improve your chances of being invited to apply. So in that case, your employer may want to get an LMIA, even though you don’t need it to be eligible.

You must complete an Express Entry profile as the first step to immigrate to Canada permanently as a skilled worker.

Source: https://www.canada.ca/en/immigration-refugees-citizenship/services/work-canada/hire-temporary-foreign/find-need-labour-market-impact-assessment.html

https://www.cic.gc.ca/english/helpcentre/answer.asp?qnum=177&top=17

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