Trainees are free to sign up for a program in the learning catalogue.
However, you can manage the number of trainees who will participate in the program.
To do so, head over the Program Settings and click on "advanced options". You can then tick "Limit the number of seats for open registration" and choose the maximum number of trainees :
If seats are no longer available for the program, any trainee who would like to sign up will have to register on a waiting list.