voluntarily

Aside from the scheduled sailings, the crew would voluntarily give up their time to put on several special "booze cruises" to raise money for island charities.

If they do not limit their profits voluntarily, they will face a legal limit on how much they can make.

Involuntary treatment is claimed to be necessary because people would not enter therapy voluntarily.

Two doctors and a High Court judge would have to verify that they were eligible, and had made their decision voluntarily.

The FDA has recommended that the individual companies voluntarily recall their products.