The legislation stipulates that, when it can be presumed that drug misuse substantially contributed to the commission of an offense, the court should consider the expressed willingness of an offender to receive treatment. According to contract treatment, the offender agrees to engage in treatment in accordance with a special treatment plan. Commentary on the legislation indicates that probation with treatment should be a possible sanction in drunk driving cases, that various forms of treatment for drug misuse should be possible in the context of contract treatment, and that the nature of the treatment need should guide the choice of treatment modality. Probation and supervision periods associated with contract treatment for drug offenders are addressed, as well as the implementation of contract treatment in practice, treatment plan issues, and offender obligations and breach of contract