Equity will assist a volunteer in some circumstances, such as when there is an imperfect gift or transfer of property. In Strong v Bird, equity perfected an imperfect inter vivos gift when the donee became the executor of the donor's estate and the donor's intention to make the gift continued until death. Proprietary estoppel is also an exception, where a volunteer relies on a promise of an interest in land and suffers detriment. The court will prevent unconscionable conduct and perfect the imperfect transfer.