Trolling is a method of fishing where one or more fishing lines, baited with lures or bait fish, are drawn through the water. This may be behind a moving boat, or by slowly winding the line in when fishing from a static position, or even sweeping the line from side-to-side, eg when fishing from a jetty. Trolling is used to catch pelagic fish such as salmon, mackerel and kingfish.

Trolling can be phonetically confused with trawling, a completely different method of fishing, where a net (trawl) is drawn through the water instead of lines. Trolling is used both for recreational and commercial fishing whereas trawling is used mainly for commercial fishing.

Trolling from a moving boat is a technique of big-game fishing and is used when fishing from boats to catch large open-water species such as tuna and marlin. Trolling is also a freshwater angling technique.
Trolling from a moving boat involves moving quite slowly through the water; this may be accomplished by use of a special trolling motor.

Many anglers troll for some or most of their fish. Trolling is the way to catch trout and salmon on lakes and reservoirs; it is the method on some muskie waters. It is a valued technique for walleye, an overlooked method for black bass, and an important means of catching striped bass. In saltwater, trolling is a critical method for catching many pelagic species, especially billfish, and important for pursuing many inshore species, including kingfish, bluefish, and various jacks. There is plenty of science and drama involved, whether the quarry is blue marlin, chinook salmon, walleye, or dolphin.

Trolling motors, or electric positioning motors, use battery power in order to propel a boat. The amount of power or strength needed to move through the water is described as "pounds of thrust." This power rating is common to all motors on the market, and is one of the most important aspects to consider when selecting the right unit to match your craft. With insufficient power behind you, working your boat through wind, high waves or weedy conditions can be all but impossible. common questions to ask yourself are: Is your boat heavy, and what is the length? Do you store a lot of gear, or fish with more than one person? Do you fish in adverse conditions, such as high winds and rough water? The following chart details the minimum amount of thrust required depending on the size of your craft. Check out these trolling motors at the Angler Store.