Official maps are ordinances, in map form, that municipalities can create to designate existing and proposed areas for public use, such as streets, schools, parks, trails, and greenways. The official map expresses a municipality’s interest in acquiring these lands for public purposes sometime in the future and notifies developers and property owners of this interest. If a landowner seeks to develop reserved land, the municipality has a year to pursue acquisition of the land from the owner before the owner may freely build or subdivide. Unless otherwise agreed upon, the law specifically states that the property owner is entitled to full market compensation.

Among their benefits, official maps enable a municipality to publicize its goals for future improvements that can help improve local quality of life. Official maps can also help a municipality prioritize and allocate its limited funding toward specific public improvement projects.