Team bonding is very important. The happiest Team with members who know each other the best are the most successful. FUN should be encouraged. Craic, humour, laughing, joking, while being professional at all times, are essential. The most successful teams I have been involved in had the most fun and socialised together more frequently. The worst performing teams had the least fun and rarely socialised together. Having Fun on the successful team was encouraged and almost compulsory where as fun on the least successful team was frowned upon and almost seen as unprofessional. Team members should feel they are important, valued members of the team but no-one should take themselves too seriously. People should not feel they need to stop being themselves.
Team building workshops/days/weekends are really valuable and important. The more you get to know someone out of the club/office strengthens your working relationship.