Specifically, it protects the assets (typically an inheritance) of the disabled person, as well as the right to collect government benefits and entitlements.
The trust beneficiary would use their personal exemptions and tax credits to reduce their taxable income.
It became of wider interest when the Supreme Court of Ontario ruled in 1989 that the trust assets were not vested in the beneficiary and thus could not be used to terminate government benefit programs.
The Ontario Ministry of Community and Social Services took his daughter to court (following a Tribunal decision overruling the case worker), arguing that she had assets.
Further, the Supreme Court explained that the money the beneficiary received from a Henson Trust is not considered an "asset", as it relates to the policy of the Metro Vancouver Housing Corp.