Our priority system works differently for TAs and Sessionals.

TA Priority
TAs have a priority system in the Collective Agreement, which gives a priority to TAs with less assignments than the number set out in the contract - for Masters students those with less than 25 base units have priority, and for PhD students, those with less than 40 base units have priority. Departments can set their own additional priorities, as long as they provide a copy of their system to the TSSU and post it prominently within the department.

Sessional Instructor Priority
For our Sessional Instructors it is more complicated. There is a priority system that gives priority to someone who has taught the identical course for a minimum of 2 semesters and where the last appointment has occurred within the last 3 years, unless there is a candidate with a Right of First Refusal or whom the department considers to have better qualifications.

Right of First Refusal provides that a Sessional Instructor who has taught the identical course for either 3 consecutive semesters or for a 5th semester within 3 years AND 3 times within the previous 9 semesters, will have the first option to teach that course. However, once they have used this right 3 times (including turning down an offer), they will lose it and have to re-earn it again. In addition, the Sessional Instructor is to inform the department chair that they have earned the right, and have this acknowledged, in order to be informed before the course is posted as a Sessional vacancy. If two people have the Right of First Refusal, there will be a competitive selection between them.