The audit examined key aspects of the first four tenders for the RtB program. These tenders provided coverage across the Basin and resulted in expenditure in excess of $1 billion. The 2008–09 tenders included the largest single purchase under the program—$303 million to Twynam Agricultural Group. The audit also examined the Commonwealth's contribution to the purchase of Toorale station, the only purchase outside a tender process.

The Civil Aviation Safety Authority (CASA) is responsible for regulating aviation safety in Australia, the safety of Australian aircraft operating overseas as well as for regulating and administering Australia's airspace. In September 2008, the Senate Committee on Rural and Regional Affairs and Transport presented a report on the Administration of the Civil Aviation Safety Authority and related matters. That report made three recommendations, one of which requested an Australian National Audit Office (ANAO) audit of CASA's implementation and administration of the regulation of aircraft operators' Safety Management Systems (SMS'). ANAO agreed to this request with the objective of the audit being to assess CASA's implementation and administration of an SMS approach to regulating aircraft operators.

An SMS is a systematic approach to managing safety, which encompasses organisational structures, accountabilities, policies and procedures. Amendments to the Convention on International Civil Aviation (commonly referred to as the Chicago Convention) made in 2006 require that contracting states regulate the SMS' of aircraft operators. As a contracting state to the Chicago Convention, Australia is required to mandate that aircraft operators implement an SMS.

On 3 February 2010, Senator Christine Milne wrote to the Auditor General raising concerns about DEWHA's administration of the Green Loans program and requesting a performance audit of the program. Issues raised included: uncapped assessor numbers; problems with the delivery of the program; the quality of assessor training and assessments provided to households; the lack of an audit facility within the program; and equitable access to work under the program.

In light of Senator Milne's request and other concerns in relation to the administration of the program, the Auditor-General agreed on 25 February 2010 to conduct a performance audit of the program. The objective of the audit was to examine key aspects of the establishment and administration of the Green Loans program by DEWHA and the program's transition to DCCEE. Particular emphasis was given to the program's three main elements:

• training, registration and contracting of assessors;
• scheduling, conduct, and reporting of home sustainability assessments, and the associated payments to assessors; and
• provision of green loans to householders, and the associated payments to participating financial institutions.

The audit also examined the extent to which steps had been taken by DEWHA and DCCEE to assess whether the Green Loans program was achieving its objectives.