<p>The Mental Capacity Act 2005 (MCA) becomes fully operational from the beginning of October. It will cover all adults (16 years old and over) in England and Wales who lack capacity, whether permanently, temporarily or in relation to some or all decisions. Scotland has its own legislation, the Adults With Incapacity (Scotland) Act 2000, which is similar to the MCA and has been in force for a number of years. The MCA does not apply to treatment for mental disorder for someone who is detained under the Mental Health Act 1983.</p>