"The new fund offers an opportunity to access the skill of these proven managers in a fund with a tiny asset level (only about $10 million at last count) and a flexible mandate. The Opportunistic and Mid Cap funds share the same investment approach.

"For both funds, the managers look for stocks with franchise characteristics (competitive advantages) and attractive valuations.

"They seek to buy these stocks before the companies enter periods of accelerating growth in profits, increasing the position sizes as operational yardsticks are met and other investors begin to notice the improved performance.

"Franchise characteristics include dominant market share, leading brands, proprietary technologies and sometimes a low-cost position in the industry.

"A purchase candidate's valuation qualifies as attractive if the stock can be purchased for at least 30% to 40% below the Artisan managers'estimate of private market value based on 'organic' growth-the value of the company's future cash flows created by internal growth and profit-margin expansion, not by acquisitions.

"To determine if a company's profits are entering an accelerating phase, the managers and their team of five experienced equity analysts examine potential catalysts for growth. Some catalysts are internal to the company in question; new-product introductions and management changes, for example.

"Other catalysts are external. They may be related to government. Reregulation or even Washington's recent 'economic stimulus' plan are two examples. Outside government, a technological change that cuts across a whole swath of the economy would be an important type of external catalyst.

"The managers also divide the portfolios of each fund among three categories they call 'Garden, Crop and Harvest.'

"The 'Garden' stocks are usually newer positions that the managers believe will enter the acceleration phase of their profit cycles fairly soon. These holdings, each of which tends to get 1% weightings in Opportunistic Growth at purchase, usually account for 20% to 25% of the funds'assets.

"The 'Crop' stocks tend to account for about half of each fund's assets. Often, these are former Garden holdings that have met yardsticks; the Artisan team will increase the weighting of each sometimes to as high as 5%, 6% or potentially even 10% of assets.

"'Harvest' stocks are approaching the end of their profit expansions, and will be trimmed or even sold outright as they reach 100% of the Artisan team's estimate of their private market values.

"In essence, the Artisan team tries to buy attractive growth stocks earlier than other investors, increase their weightings in the companies as they reach certain operational milestones.

"Opportunistic Growth can invest in a stock of any size as long as it's above $3 billion. Also, the new fund has a relatively focused portfolio of between 30 and 50 stocks, can invest up to 25% of assets internationally.

"Stephens notes that he and his co-managers are currently emphasizing 'early cycle' stocks. Most of the assets reside in stocks in one of four sectors: technology (28% of assets as of March 31), consumer discretionary (18.3%), healthcare (17.6%) and financials (14.1%).

"Whatever their sector or industry, most of the stocks in the fund are highly innovative companies that are among the leaders in their fields.

"And, because of the horrible stock market from October 2007 until early March 2009, most of the holdings have p/e ratios that appear very reasonable now, given the companies'quality and potential.

"Though a few of the holdings have very large market capitalizations, the bulk would be considered on the large side of mid cap or the small side of large cap.

"Opportunistic Growth had a rough go of it in its first few months of existence but has performed strongly so far in 2009. It'sup 13% for the first four months of the year, good enough for seventh among nearly 250 funds in. We recommend it highly as part of the aggressive portion of an investor'sequity allocation."

Steven Halpern's TheStockAdvisors.com offers a free daily overview of the favorite stock picks and investment ideas from the nation's leading financial newsletter advisors.