The club does not require players to have convention cards in most circumstances. However if you are a strong player playing with a regular partner, the committee think it would be a courtesy for you to have a card for the benefit of your opponents.
Members should also note the practical benefits of having a completed convention card. If you have a bidding misunderstanding the director is required to assume that partner has given the wrong explanation (rather than that you have made the wrong bid), unless there is firm evidence to the contrary; thus,without a card you will likely to be ruled against.
The club requires players to have a convention card if any of the following apply: