A business can extract all kinds of benefits from a dominant market position. To name just two examples, the industry leader typically posts higher profitability and stronger, more consistent sales gains.

Below, Motley Fool investors highlight three growth stocks that have this rare but valuable asset -- a virtual monopoly. Let's see how iRobot (NASDAQ:IRBT), Brookfield Infrastructure Partners (NYSE:BIP), and MercadoLibre (NASDAQ:MELI) are taking advantage of theirs today.

An army of robotic cleaners

Demitri Kalogeropoulos (iRobot): If you paid over $200 for your vacuum, you may have bought the device from iRobot -- the robotic cleaning specialist is responsible for 64% of all global spending on premium vacuums. Its dominance is even more pronounced in the robotic niche, where it sold 88% of all autonomous vacuums in the U.S. last year.

A man reclines on a couch while a robotic vacuum cleans the floor.

Image source: Getty Images.

That prime market position is translating into efficient growth. Sales were up 22% last quarter, including a 34% spike in the core U.S. market. iRobot is getting more profitable, too. Gross margin is up to 50% of sales so far in 2017, compared to 47.5% in the prior-year period.

The company's stock has dropped recently as Wall Street worries about the threat that competition, at both the premium and the value ends of the market, could erode iRobot's big industry lead. The company's deep portfolio of patents should help it defend itself through innovation, though.

Even if iRobot loses some ground, its sales outlook is bright, considering how much room the industry has for expansion. Robotic vacuums are only found in 10% of homes in the U.S. today, and that number could grow significantly as features improve and prices fall.

The power of monopolies all over the world

Jason Hall (Brookfield Infrastructure Partners L.P.): Brookfield Infrastructure owns 35 separate businesses in 15 countries. And many of those businesses, which are composed of critically important infrastructure assets in the utility, water, energy, telecommunications, and transportation sectors, are monopolies -- they supply water, electricity, telecommunications, or highway access to areas with no competition.

The downside is that prices are almost always regulated to prevent the company from holding the communities it serves over a barrel. But the upside consists of steady, predictable cash flows, and lower risk of competitors trying to move in.

Infrastructure is a huge global growth industry. The global population is adding nearly a billion people every 15 years, and the majority of those people will live in cities. That will drive tens of trillions of dollars in global investments over the next few decades to expand and modernize water supply and treatment facilities, telecom data capacity (including fiber and cellular data), and municipal infrastructure such as smart meters and other connected technologies that will drive the cities of the future.

And with its global operations, Brookfield Infrastructure is already taking advantage of those growth prospects. Funds from operations are up 14% per share, year to date, and increased almost 20% in the third quarter. With a dividend yield of just under 4%, and a track record that should continue driving the payout higher every year, Brookfield Infrastructure is my favorite monopoly-type business to own. Trading for about 14 times expected 2017 FFO, it's reasonably priced considering the quality of the business and its long-term growth prospects.

Un cuasi-monopolio para usted

Dan Caplinger (MercadoLibre): Companies that successfully dominate a large geographical area can fairly claim monopoly status, even if they face global competitive threats elsewhere. That's the case with MercadoLibre, currently the biggest player in the e-commerce industry in Latin America. With considerable exposure to key economies including Brazil, Mexico, and Argentina, MercadoLibre casts a wide net across the South American continent that also extends northward into Central America. And the recent success of those economies has helped propel the e-commerce giant's business prospects higher.

A man holds a credit card while typing into a tablet.

Image source: Getty Images.

MercadoLibre's status as a near-monopoly extends to its development of a well-established vertically integrated business model. Like its counterparts to the north, MercadoLibre has established an electronic payments network, a shipping service, methods to provide financing to purchasers, and other conveniences that fit well with its online marketplaces.

The company isn't completely immune to competition, and some observers fear that e-commerce players from outside the region will see its success and move in to claim their share. Yet with a substantial home-market advantage and extreme customer loyalty from a growing consumer base, MercadoLibre will be tough to beat for any company seeking to come in and challenge its dominance of the region. Investors hoping to participate in that success should look closely at the stock of this Latin American e-commerce player.

Dan Caplinger has no position in any of the stocks mentioned. Demitrios Kalogeropoulos has no position in any of the stocks mentioned. Jason Hall owns shares of Brookfield Infrastructure Partners, iRobot, and MercadoLibre. The Motley Fool owns shares of and recommends iRobot and MercadoLibre. The Motley Fool recommends Brookfield Infrastructure Partners. The Motley Fool has a disclosure policy.