The Preliminary Engineering and Design phase defines the overall project configuration that has elements applicable to both construction and non-construction projects. This is usually the first phase of a local government (LG) project that follows after execution of the Advance Funding Agreement (AFA) between TxDOT and the LG. This phase includes four elements: State Letter of Authority (or Notice to Proceed); procurement of professional services; design schematic and layouts; and early phases of design (also considered to be the plans, specifications and estimates at 30 percent completion). Preliminary studies may be performed in this phase, including environmental assessments, surveys, geotechnical studies, hydrologic/hydraulic analyses, traffic studies, etc. This chapter of the Local Government Projects Policy Manual (LGPP Manual) provides the laws and regulations which the LG and TxDOT must use to satisfy the requirements for a State Letter of Authority (SLOA), the procurement of services and the design of the project components. The companion document, (LGPM Guide), provides the procedures and practices for implementing these regulations.