Abstract: Connectors for joining adjacent modular floor covering units. The connectors include a base or film and one or more attachment members. As an exemplary use of a connector to install tiles, a first tile is placed on the floor and a connector is positioned so that an attachment member faces upward and attaches to the first tile. One or more other tiles are then positioned adjacent the first tile so that the same or other attachment members of the connector attach to the adjacent tiles. In certain embodiments, an attachment member comprises projections that form a mechanical connection with the undersides of the tiles. For example, a connector may comprise a plastic unit with raised ridges that interact with corresponding indentations on the undersides of the tiles. A connector can also or alternatively form a connection with tiles and/or the underlying floor surface by having a high coefficient of friction.