The "Zero-Based Budget Act" requires the State Treasurer to implement zero-based budgeting practices for the preparation of the Governor's annual budget message, with a start date for fiscal years on or after July 1, 2012. This approach mandates that state spending agencies justify their budget requests based on the cost-effective achievement of their goals, rather than relying on previous fiscal year allocations. Agencies must submit detailed justifications that include their goals, activities, legal authority, methodologies, and evaluations of service quality, thereby promoting a thorough evaluation of current programs to prioritize funding effectively amid economic uncertainties.

Key amendments in the bill include replacing references to the "Department of Taxation and Finance" with the "Department of the Treasury" and changing the term "commissioner" to "State Treasurer" in various sections, highlighting the Treasurer's role in the budgeting process. Additionally, all applications for supplemental appropriations must be filed with the State Treasurer, who will certify and transmit these applications to the Governor for review and recommendations based on available funds. The act aims to enhance transparency and accountability in state budgeting by ensuring that all spending requests are rigorously evaluated and justified.