The Pathfinder Project, sometimes known informally as Project Voyager, was the title of a late 24th century Starfleet Communications project that attempted to communicate with USS Voyager, which was stranded in the Delta Quadrant.
The Project was established sometime after 2374, following the discovery of Voyager's presence in the Delta Quadrant when The Doctor was sent to the USS Prometheus. It was overseen by Admiral Owen Paris, and was based at Starfleet's Communications Research Center.
The day-to-day running of the project was handled by Commander Peter Harkins, and its staff included Lieutenant Reginald Barclay. Deep Space 9 also assisted the project by providing interstellar phenomena forecasts.
Pathfinder first made contact with Voyager in 2376, using the Mutara Interdimensional Deep Space Array System to create a micro-wormhole. This first communication, though brief and problematic – allowed Admiral Paris to talk to Captain Kathryn Janeway, who assured him that his son was performing well – the communications technology improved to a level whereby contact could be made on a regular basis. (VOY: "Pathfinder")
By the following year, the crew was able to receive monthly data streams from Earth that included letters from the crew's families, tactical upgrades, and news about the Alpha Quadrant. By 2378, Operation Watson resulted in two-way visual communication every day for eleven minutes. (VOY: "Life Line", "Inside Man", "Author, Author", "Endgame")