Joining the same Group allows others to contact you using the Group messaging feature. Which LinkedIn Groups should you join? You don’t have to join the maximum 50, but at least join a few groups that are related to your industry, discipline, or location – not to mention alumni groups from your university or even previous workplaces. If you haven’t been active in groups before, you might be surprised as to the business opportunities that exist within LinkedIn Groups! Even if you don’t have time to be active, displaying those group logos on your profile increases your contactability.