A terminal strip assembly of an electrical conductor terminating system includes a first insulating terminal support block having an essentially M-shaped configuration, with a transverse bight portion, rows of electrical conductor guide portions projecting in a first direction from the same side of the bight portion, and resilient side legs projecting in a reverse direction from locations adjacent an opposite side of the bight portion. A row of U-shaped terminals is mounted on the first support block and each terminal includes bifurcated legs which extend within respective adjacent ones of the guide portions to receive electrical conductors inserted between the guide portions. A connector plug assembly for use with the terminal strip assembly includes a second insulating terminal support block having a row of essentially J-shaped electrical conductor terminals mounted thereon. One leg of each of these terminals extends within a pair of respective adjacent electrical conductor guide portions of the second support block. A second leg of each of the J-shaped terminals projects into a channel in the second support block so that the second leg is received in a respective one of the bifurcated terminal legs of the U-shaped terminals in the first support block when the connector plug assembly is plugged onto the terminal strip assembly. Releasably mounted members on the terminal support blocks retain the U-shaped terminals and the J-shaped terminals on the support blocks.