What do employment-at-will and for cause mean?

Employment at will means that the employer does not need a reason, nor does the employee need a reason, to terminate the employment relationship. It can be terminable at any point in time with or without any reason. A cause provision, by contrast, requires there be a good reason for it: for example, poor performance, or not showing up, or not completing assignments, or insubordination. There can be good reasons, and that’s what’s considered a cause provision.