| Year | Type | Date | Effective Date | Letter Number | Subject | |
2012 | |
| General Letter | |
| | 01/30/2012 | 02/01/2012 | G-2012-02 | Revisions to Engineering Policy Guide |  |
| | 01/30/2012 | 02/01/2012 | G-2012-01 | Revisions to Job Special Provisions |  |
| Specifications Letter | |
| | 01/30/2011 | 02/01/2012 | S-2012-01 | Revised Supplement to the Standard Specifications |  |
| Standard Plans Letter | |
| | 01/30/2012 | 02/01/2012 | P-2012-01 | Supplemental Revisions to Missouri Standard Plans for Highway Construction |  |
2011 | |
| Design Manual Letter | |
| | 06/22/2011 | 07/01/2011 | D-2011-03 | Revisions to Engineering Policy Guide |  |
| | 03/31/2011 | 04/01/2011 | D-2011-02 | Revisions to the Engineering Policy Guide |  |
| | 01/03/2011 | 02/01/2011 | D-2011-01 | Revisions to the Engineering Policy Guide |  |
| General Letter | |
| | 09/07/2011 | 10/01/2011 | G-2011-06 | Computer Stored Pay Items |  |
| | 06/22/2011 | 07/01/2011 | G-2011-05 | Revision to Job Special Provisions |  |
| | 05/25/2011 | 06/01/2011 | G-2011-04 | Computer Stored Pay Items |  |
| | 03/28/2011 | 04/01/2011 | G-2011-03 | Computer Stored Pay Items |  |
| | 01/03/2011 | 02/01/2011 | G-2011-02 | Computer Stored Pay Items |  |
| | 01/03/2011 | 02/01/2011 | G-2011-01 | Revisions to Job Special Provisions |  |
| Specifications Letter | |
| | 11/16/2001 | 12/01/2011 | S-2011-05 | Revised Supplement to the Standard Specifications |  |
| | 09/01/2011 | 10/01/2011 | S-2011-04 | Revised Supplement to the Standard Specifications |  |
| | 06/22/2011 | 07/01/2011 | S-2011-03 | Revised Supplement to the Standard Specifications |  |
| | 03/28/2011 | 04/01/2011 | S-2011-02 | Revised Supplement to the Standard Specifications |  |
| | 01/03/2011 | 02/01/2011 | S-2011-01 | Revised Supplement to the Standard Specifications |  |
| Standard Plans Letter | |
| | 11/16/2011 | 12/01/2011 | P-2011-05 | Supplemental Revisions to Missouri Standard Plans for Highway Construction |  |
| | 09/01/2011 | 10/01/2011 | P-2011-04 | Supplemental Revisions to Missouri Standard Plans for Highway Construction |  |
| | 06/22/2011 | 07/01/2011 | P-2011-03 | Supplemental Revisions to the Missouri Standard Plans for Highway Constructions |  |