First of all, the very first digit of each suite number always reveals the floor on which each suite is located, from one to five. Then, the second and third digits effectively reveal how far south or north each suite is located, with "01" being the farthest south. Franson Family Chiropractic, for instance, is Suite 101-D. It is therefore on the first floor at the extreme south end of 100 Cummings Center, closest to Elliott Street. Hamilton Thorne Biosciences, on the other hand, is in Suite 465-E, which means it is on the fourth floor near the extreme opposite north end of Building 100.

(The structural columns in all buildings except 500 and 950 are located 20'-0" on-center each way, beginning with column "01" near the south end of Building 100, and ending in Building 100 with column "66" near the far north end. Columns run south to north in Building 900 from "01" to "30," Building 800 from "47" to "66," Building 600 from "65" to "76," and Building 200 from "71" to "82.")

The fourth element of each suite number, of course, is an upper-case letter. These letters run from "A" through "E" in Building 200, "A" through "Q" in Building 100, "R" through "W" in Building 900, "R" through "X" in Building 800, and "X" through "Z" in Building 600. All of these letters designate each suite's position on the east-to-west grid. All units with addresses ending in A, B, or C will mostly have their entrances from a hallway along the far east side of Building 100, along the railroad right of way.

Looking (above) at the south elevation of 100 and 900 Cummings Center, note that Suite 101-D is on the far right (east) end of Building 100, while Suite 101-K is near the center, and Suite 101-N is more to the left side of the structure. Moving across Center Drive, Suite 101-T is in the center of Building 900.

Both 500 and 950 Cummings Center follow their own numbering systems. Suites at Building 950 are numbered "96" through "108" from the southeast end of the building to the northwest corner and incorporate letters "X" and "Y" into the suite addresses.

Building 500 follows a simple numbering system. the first digit of each suite number reveals the floor on which each suite is located, from one to six. Then, the second, third, and fourth digits effectively reveal how far west or east each suite is located, with "000" being the farthest west and "999" being the east.