If you can catch a walleye on something as simple as a Lindy rig, then why would you add something as complicated as an electric downrigger to your boat?
The answer is just as basic as a slip-sinker and hook: to catch more walleyes when simple techniques don’t work as well.
That’s not to say that you can’t catch walleyes rigging or jigging most of the time because you can; however, there are times and places where downriggers really shine.
Where and when?  Well, take Lake of the Woods for example.  Here’s a big lake where ‘eyes will scatter in a hundred different directions.  Yeah, they’ll relate to structure and roam in schools, but those pieces of structure—reefs mostly—are scattered, and the walleye schools will be as well. 
You can pinpoint, target and catch walleyes with rigs or jigs or floats in those conditions, but (and this is a big “but”) it can be a slow process finding fish.

Lake of the Woods walleye guru Nick Painovich has walleyes and downriggers dialed in. What he’s found, and the techniques he uses, are applicable anywhere you find walleyes on larger lakes.
“Generally,” says Painovich, “we’ll start fishing with downriggers as soon as the walleyes move to deeper water. Up here, that’s as early as June, and we’ll continue to use them through July and August into September.”
Painovich isn’t just a weekend fisherman; he and his wife Deanna own Zippel Bay Resort on the south side of the big lake, and Nick is one of the most knowledgeable charter skippers on the lake.
His nearly daily trips have shown him that downriggers have their place.  Maybe that’s why he runs six (and sometimes more) off his charter boats.
“Downriggers give you accurate depth control,” Painovich says. “And that’s important when you’re fishing over structure that varies in depth.  You have to know exactly where your downrigger weights are.”
Painovich matches his downriggers with deep-diving crankbaits, an unusual approach, but one that makes sense when it’s explained to you.  “Since diving crankbaits run below the ball,” he says, “you don’t have to run that close to the bottom.
“You can dial in exactly what depth you need to put the crankbait in the walleye zone without running the risk of hanging your ball on the bottom.”

While a range of crankbaits will work on downriggers, it’s no surprise that Painovich likes Lindy’s Shadling.
“These crankbaits are good behind downriggers for several reasons,” Painovich says.
“First, they run straight right out of the box; no tuning is necessary.
“Second, and just as important, you can run them fast-- up to six miles an hour-- without them rolling.  That’s really important when you’re fighting the wind and need a faster speed than normal
“Third, they come in a good range of colors and two effective sizes, so you’ve got a crankbait that will appeal to walleyes on any given day.”
Painovich stresses that just hanging a Shadling or other crankbait on a release isn’t enough to guarantee you walleyes.  Like any other type of walleye fishing, it takes experimentation to find the right combination on any given day and on any given hour.
“You really need to mix it up,” he says, “until you find the right combination of location, depth, dropback, color and size.” Once you start catching walleyes, it’s only a matter of staying on the school.
Painovich starts the day by heading toward deep structure. In the case of Lake of the Woods, that is offshore reefs, but it could be sunken islands or extended points—anywhere he can expect to find the right kind of deep water with a change in depth.
“In July and August,” he says, “I’ll head toward the main lake basin.  That’s where I’ll find bigger fish.  I’ll troll edges and the deep part of the drop off. I’ll troll over the tops of the deeper features and will find big fish.”
He also adds that having a depthfinder/GPS with a chip for the lake is a big help in both locating structure he wants to fish as well as setting up repetitive passes over productive water.
While finding the fish is the first step; it’s not the only one on the way to a full livewell. You gotta have the right lure of the right color at the right depth at the right time.
And you’ve got to present it the right way.  Some of that is related to speed. While Painovich notes that he sometimes has to troll faster than he’d like to offset the effects of wind on his 30-foot charter boat, he finds that a trolling speed somewhere between 2.5 and 3.0 miles per hour is more to the walleye’s liking.
“Another thing you’ve got to tune in is setback.”  Setback is the distance your lure runs behind the downrigger weight.  “I will run 20, 30 even 35 feet behind the ball,” Painovich says.  “That way I figure the Shadling is running maybe five feet below the weight.”
He’ll then play with depth to find the zone in which the fish are feeding, raising or lowering the downrigger ball until he starts getting bit.
Of course, color plays a big part in trolling success, and Painovich says that it will change with the time of day, the strength of the wind and the clarity of the water.
“In the morning, I’ll run darker finishes,” he says. “Blues, John Deere green, purple—these colors are good for mornings and will work all day if it’s overcast or windy”, conditions that cut down the light.
“When it is brighter, I like silvers, chartreuses, brighter colors.  Of course, the silver/black finish is usually good any time.”
Size is another thing that plays an important part in the puzzle that is walleye.  Painovich is stuck on the Lindy Shadling and usually runs the number 5 size, but he’ll go up to a 7 if he’s after larger fish.  Obviously, other crankbaits will work, but use the Shadling as a comparison for sizes to get the general idea.

Of course, you can also fish spinners or spoons behind a downrigger.  Painovich will pull spoons, but he’s found that’s good pike medicine and not as effective on walleyes. “However, I’ve caught some big walleyes on spoons when fishing for suspended pike.”
In other waters, downriggers also give walleye fishermen the ability to target suspended schools of walleyes.  Any time you have fish that hold independent of the bottom, downriggers can make the difference in catching or not.
Whether the walleyes are suspended and chasing schools of free-roaming baitfish or holding off edges and points, waiting to move up to feed, the accurate depth control and the ability to repeat pass after pass will put more fish in the boat.
And downriggers are the perfect tool to give you that control.