Electrification of the main ÖBB Arlberg line in the 1920's at 15Kv AC. gave the MBS an unwanted problem. For a while the MBS electric trains were powered into and out of Bludenz by steam engines, a process both slow and costly. Accumulator cars were tried, and the electrical equipment of electric unit ET 10.103 was altered to work of both power supplies, but eventually the only solution was found to be the changing of the supply, in 1972, to match the main line. Prior to this, the freight traffic for the construction of three reseviors in the area (the Vermuntstausee, the Silverettastausee and the Kopsstausee) had forced the use of hired-in diesel locomotives becasue of a lack of suitably powerful engines.

Starting in December 2002, MBS commenced running off their own line, and indeed became an International train service provider, running a service wach way daily between the island town of Lindau, in Germany, via Bregenz to Bludenz and thence to Schruns. Goods traffic continues, including timber traffice from the whole length of the route, and cement traffic from the works at Lorüns, together with some goods to and from the Voralberger Ilwerke hydro-electric plant at Tschagguns. Montafonerbahn AG, the parent company, also operate power generation, cable television, and electricity and water supply companies in the region.

In connection with the building of the Vermuntsee resevoir above Partentumin in 1928, a 760mm gauge line was built from the goods yard at Tschaggens, through the streets of Schruns, and alongside the road up the Ill Valley. A funicular (now replaced by a goods lift) was constructed to take materials up the mountain to Untertrominier, where another 760 mm gauge line was built, partly underground, to the dam. The lines were built by Voralberger Ilwerke, who operate the hydro-electric scheme to this day. The track through Schruns was removed when the road system in Schruns was altered in the early 1980's. However the VIW bahnhof at Tschaggens still exists, with a small display of narrow gauge rolling stock, including a Schmalspurtiefladewagen. The route to the Vermuntsee above Partenen is a public footpath today.

Plans have been announced to extend the MBS beyond Schruns to Partenen, but so far no detailed surveys have been completed.

The railway has a large collection of electric railcars and locomotives, and also operates steam-hauled summer services. Most vehicles, when not in use, are stabled in or around the works and depot, beyond the platforms at Schruns.

Models in H0 are available from Roco of both the ex OBB 1045 and the bogie copaches.

A 6 page article on the Montafonerbahn by ARG member Peter Marriott appeared in Continental Modeller September 2007 with 19 illustrations and a layour plan for Schruns.