The Japanese do not really undertake training sessions on teambuilding — they are naturally group-oriented which underlies the need for a truly consensus approach to issues.
The consensus-building process or nemawashi (literally root binding) determines that agreement is sought before a formal meeting in order to avoid any direct confrontation. Thus arriving at a meeting expecting issues to be thrashed out in a direct and forthright manner will almost always lead to disappointment.
It is also important that group members maintain face in front of other group members, which amongst other things means that people must be seen to be modest and humble. Self-promotion in the western sense is seen as childish and embarrassing behaviour.
The group or groups to which a person belongs are a life-defining set of relationships and the importance of these group relationships should never be underestimated. Therefore, Japanese businessmen (and women) will often socialise in teams after work. Dinner and drinks are an important work and social function and should be encouraged.