A multiple entry visa allows you to enter and leave Sweden and other Schengen countries multiple times during the visa validity period. You can travel in and out without applying for a new visa each time. This is useful for people who travel frequently for tourism, business, or family visits. The visa can be valid for several months or even years, depending on approval. However, you must still follow the rule of staying only up to 90 days within a 180-day period.