The 101 problems discussed in this guide have been classified alphabetically into 19 repair techniques, each starting with a discussion followed by one or more problems (questions) with the answers. The topics are: acid etching and washing; bonding; cleaning, removing stains and discoloration; crack and joint repairing; evaluating damage; grooving and grinding; grouting; leveling; liquid floor hardening; overlaying; painting, coating, and lining; patching; plastering; resurfacing; sawing, drilling, and cutting; shotcreting; slabjacking; underwater repairing; and waterproofing. While there is a wealth of information in this issue, ti should be noted that the 101 items included have been assembled by culling from the extensive CONCRETE CONSTRUCTION Problem Clinic files; the result is that this issue is by no mens a complete treatment of the subject of repair, although an attempt has been made to cover as many repair techniques as we could find in our voluminous collection.