~3-page information security policy template on contractors and consultants.
 
Support staff and other professionals employed by third-parties or self-employed but working on behalf of and under the control of the organisation are subject to essentially the same information security policies and obligations as employees.  This policy clarifies those obligations and describes a few supplementary information security controls relating to the commercial relationships involved.
 
Supplied as an MS Word document, readily customised for your organisation's specific situation.