The tests of testamentary capacity are generally well understood and the standard has been static for many decades. However, what level of capacity is required to make an inter vivos gift? This was considered in Re Estate Joyce where it was held that the test remains that of Re Beaney, which requires:
The quantum of the gift is also relevant and the where the transaction is significant – these require a more considered approach to determine that the requisite capacity existed at the time of the gift.
Where a gift is unwise, the gift will not be found to be invalid only because the gift was unwise, provided that the other tests are satisfied. This can be considered alongside the common law regarding testamentary capacity where a testator’s inability to understand the consequence’s of a will does not invalidate it (Simon v Byford).
While not essential, prudent practice can be to follow the checklist in the Assessment of Mental Capacity: A practical guide for doctors and lawyers published by the British Medical Association (BMA). See the Hong Kong decision in Choy Po Chun v Au Wing Lun  HKCA 210 where the Court noted the failure to follow the BMA checklist. Also see Mok HIng Chung v Wong Kwong Yiu  HKCA 452 for a contemporary consideration of testamentary capacity.