Interstate 795 (I-795), also known as the Northwest Expressway, is a nine-mile (14 km) freeway linking Baltimore's northwestern suburbs of Pikesville, Owings Mills and Reisterstown, Maryland to the Baltimore Beltway (Interstate 695). The route bypasses Maryland Route 140 (MD 140), Reisterstown Road), carrying part of the Baltimore Metro Subway in its median for a four-mile stretch, and provides direct access to Owings Mills Mall. It never connects to its parent, I-95, except via I-695.

I-795 begins in Pikesville at a directional T interchange with I-695 (Baltimore Beltway), which heads south toward Glen Burnie and east toward Towson. I-695 provides access to I-95 in the directions of Washington and New York and to highways into Baltimore. Immediately to the east of the interchange is the Old Court station of the Baltimore Metro Subway, which passes through the interchange and settles into the median of the six-lane freeway as they cross Gwynns Falls. I-795 parallels and has two crossings of CSX Transportation's Hanover Subdivision as the freeway and transit line head northwest. The subway line ends just north of its and the highway's second crossing of Gwynns Falls at the terminal Owings Mills station.

Immediately to the northwest of the subway terminus is I-795's interchange with Owings Mills Boulevard (unsigned MD 940), which is a partial cloverleaf interchange with flyover ramps from northbound I-795 to southbound Owings Mills Boulevard and from the southbound boulevard to the southbound Interstate. The interchange also features direct ramps with Owings Mills Town Center to and from the direction of Baltimore and direct ramps with the subway station to and from the direction of Reisterstown. I-795 continues northwest as a four-lane freeway. The highway has a partial cloverleaf interchange with Franklin Boulevard before reaching its northern terminus at MD 140 on the edge of Reisterstown. The terminus consists of direct ramps with MD 140 to and from the direction of Westminster and an intersection with MD 140 (Westminster Pike) and MD 795, an unnamed and unsigned connector between the intersection and an intersection with MD 30 and MD 128 on the north side of Reisterstown.

The Northwest Expressway was one of the first freeways planned for construction in the state of Maryland. The first four-mile (6 km) section to the Owings Mills exit was completed in 1985; the remaining five miles (8 km) were completed in 1987.

The original plan was for the highway to run into the City of Baltimore along a similar route to that of the Metro Subway. Plans to extend the highway beyond its current configuration have not been sought out by highway officials in Maryland. This alignment would most likely have terminated at Wabash Avenue, which parallels the elevated section of the Metro Subway.

The entire route is in Baltimore County.