Exchange-traded funds offer a convenient way to invest in sectors or niches that interest you. If you'd like to add some solid dividend-paying and dividend-increasing stocks to your portfolio but don't have the time or expertise to hand-pick a few, the ProShares S&P 500 Aristocrats ETF (NYSEMKT:NOBL) could save you a lot of trouble. Instead of trying to figure out which stocks will perform best, you can use this Dividend Aristocrats ETF to invest in lots of them simultaneously.

The basics
ETFs often sport lower expense ratios than their mutual fund cousins. This ETF, focused on Dividend Aristocrats in the S&P 500, sports a relatively low expense ratio -- an annual fee -- of 0.35%. The fund is fairly small, too, so if you're thinking of buying, beware of possibly large spreads between its bid and ask prices. Consider using a limit order if you want to buy in.

This Dividend Aristocrats ETF is too young to have a sufficient track record to assess. As with most investments, of course, we can't expect outstanding performances in every quarter or year. Investors with conviction need to wait for their holdings to deliver.

Why dividend aristocrats?
The power of dividends is often underappreciated and worth putting to work in your portfolio. Companies deemed "Dividend Aristocrats" have hiked their dividends each year for at least 25 years. They're a promising bunch of companies, but they do vary in their appeal, as some may not have big yields or may not be increasing their payouts significantly.

More than a handful of Dividend Aristocrats had strong performances over the past year. Walgreen Co. (NASDAQ:WBA), for example, surged 39% and yields 1.9%. Its payout has been growing aggressively, with an average annual increase topping 20%. Its last quarter was solid, with higher sales making up for lower traffic. The company announced plans to close some locations, but it will be opening more, making a net gain. Walgreen has also been taking some Medicare Part D market share from rival CVS Caremark.

AbbVie (NYSE:ABBV) jumped 20%. Split off from Abbott Laboratories and focusing on pharmaceuticals, AbbVie yields 3.2%. Its blockbuster rheumatoid arthritis drug Humira contributes a huge chunk of revenue (its $10.7 billion in 2013 was 56% of AbbVie's total revenue) and faces patent expiration in 2016, but it's being tested for additional indications and still holds much potential. Bulls are optimistic about its pipeline, which includes treatments for Hepatitis C, among other things.

Sherwin-Williams Company (NYSE:SHW) gained 17% and yields 1.1%. The paint giant had hoped to expand in Latin America via a purchase of the paint operations of Mexico's largest paint-supplier, but that deal recently fell through. The stock's price seems appealing, with a forward price-to-earnings (P/E) ratio near 13, well below the five-year average of 21.5. Sherwin-Williams reports its first-quarter results on April 17. Its fourth quarter featured revenue up 11% over year-ago levels, in part due to acquisitions, though earnings came in below expectations. It's poised to benefit from the recovering housing market, but it faces competition, too.

Other Dividend Aristocrats didn't do quite so well over the last year but could see their fortunes change in the coming years. Procter & Gamble Company (NYSE:PG) advanced just 6% and yields 3%. The company has been struggling in recent years and brought back its former CEO to try and boost performance. The company just announced plans to sell most of its pet food business to Mars for $2.9 billion as it restructures, focusing on its core businesses. Two months ago it announced plans to sell its bleach business, too. Procter & Gamble's second quarter was solid, with 3% organic revenue growth and efficiency improvements. Its forward P/E above 17 makes the stock seem far from a screaming bargain, but it's a consumer brands powerhouse that's likely to keep growing steadily.

The big picture
If you're interested in adding some Dividend Aristocrats to your portfolio, consider doing so via an ETF. A well-chosen ETF can grant you instant diversification across any industry or group of companies -- and make investing in and profiting from it that much easier.