Role of a co-supervisor, if appointed

Not everyone will need a co-supervisor as many supervisors have all the knowledge and skills needed to give you good advice. However, in some cases your supervisor may judge that it will be helpful for you to have a co-supervisor who can complement his/her advice by contributing specific skills or knowledge, about, for example, methodological detail, statistical techniques or the topic studied. It is up to the supervisor to arrange co-supervision having discussed with you your individual needs.