Leos are the youth organisation of Lions. Leos do very similar activities to Lions, however as they often have more time to donate than money, their service activities vary from traditional Lions activities. 

There are two types of Leo Clubs: Alpha and Omega Leos. Alpha Leos are up to 18 years of age whereas Omega Leos are between the age of 16 to 30. In Europe there are mostly Omega Leo Clubs.

European Leo Clubs are organized by each country but there is an European council called the International Liaison Officers Council (ILOs). For every forum and conference the Leos districts will define a delegation leader (DL) who will lead the delegation and ensure their practical needs are met.

ILOs and DLs work together on coming up with motions for the constitution of LEF, which, by the nature of it, also defines the work of Leos all over Europe.