Updating a TIP must be consistent with the STIP development process;

Modifications to a currently approved TIP can be made as defined by state law;

The TIP is approved by the MPO and by the Governor's designee (TTC or TxDOT Executive Director). After approval, the TIP must be included without modification into the STIP except in nonattainment and maintenance areas where a conformity finding (i.e., a determination that a transportation plan, project, or improvement program will not violate air quality standards) by the FHWA and the FTA must be made before it is included in the STIP;

All TIPs must be financially constrained and are merged into the STIP. Generally, a project's letting year is established as part of placing it in the TIP;

Federal regulations require that projects proposing to use federal funds are shown in the TIP before project approval. Projects that will not use federal funds, but that will require approval by federal agencies (such as conformity with the Clean Air Act) must also be in the TIP;

In nonattainment areas or maintenance areas, all Regionally Significant projects, regardless of funding (federal, state or local), must be in the Statewide Implementation Plan (SIP) (see );

In nonattainment and maintenance areas, the TIP and MTP must be found to conform with the SIP. The projects in the TIP must contribute to a reduction in emissions;

In all areas, locally funded, Regionally Significant projects let in the previous fiscal year, must be listed in the Annual Project List provided to the FHWA/FTA at the end of the fiscal year for every year in the TIP/STIP;

The STIP must be consistent with expected funding levels and is fiscally constrained;

Before approval of the STIP, there must be an opportunity for public comment;

All projects listed in the STIP must be included in a TIP and MTP (MTP only where applicable);

All federal-aid projects must be included in the STIP before federal funds may be authorized for the phase of project development and before federal reimbursement of work will be authorized; and

Federal Project Authorization and Agreement (FPAA) (see ) to obligate federal funds must be obtained before incurring reimbursable project costs.