Session session=...; session.getTransaction().begin(); Club club = session.get( Club.class,1 ); Person p1 = new Person(...); Person p2 = new Person(...); session.save( p1 ); session.save( p2 ); session.flush(); club.getMembers().add( p1 ); club.getMembers().add( p2 ); session.getTransaction().commit(); // will actually resolve to false! assert club.getMembers().contains( p1 );