Summary Prospectus by Investment Company (Form 497K)

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Business Quality-The team uses a variety of sources to understand the resiliency of an issuer's business model. The team analyzes the general health of the industry in which an issuer operates, the issuer's competitive position, barriers to entry, the dynamics of industry participants, and the decision-making history of the issuer's management and, when applicable, financial equity sponsor. As part of the team's analysis of a company's business quality, among other factors, the team considers certain environmental, social and governance ("ESG") factors relating to the company. These ESG factors may include the impact of environmental regulatory change, the use of human, natural and physical resources and corporate governance structures and practices. When the team deems a factor material to the value of a company, the team incorporates it into its decision-making process.

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Financial Strength and Flexibility-The team believes that analyzing the history and trend of free cash flow generation is critical to understanding an issuer's financial health. The team's financial analysis also considers an issuer's capital structure, refinancing options, asset or collateral coverage, financial covenants, amortization schedules and overall financial transparency.

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Downside Analysis-The team believes that credit instruments by their nature have an asymmetric risk profile. The risk of loss is often greater than the potential for gain, particularly when looking at below investment grade issuers. The team seeks to manage this risk with what it believes to be conservative financial projections that account for industry position, competitive dynamics and positioning within the capital structure.

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Value Identification-The team uses multiple metrics to determine the value of an investment opportunity. The team looks for credit improvement potential, relative value within an issuer's capital structure and against industry peers, catalysts for business improvement and potential value stemming from market or industry dislocations and/or mergers and acquisitions ("M&A").

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Market Risks-Markets may perform poorly and the securities in which the Fund invests may underperform the general securities markets. Securities markets may experience periods of high volatility and reduced liquidity in response to governmental actions, intervention and/or policies, economic or market developments, or other external factors. The value of a company's securities may rise or fall in response to company, market, economic, political, regulatory or other news.

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Active Management Risks-The success of the Fund is dependent on the team's investment decisions, which are based, in part, on the research process employed by the team. The portfolio securities selected by the team may decline in value or not increase in value when the market indices, including relevant benchmark indices, are rising, in which case the Fund could experience losses regardless of the performance of the market indices. When the team considers ESG factors in its research process, the Fund may forgo certain investment opportunities and underperform funds that do not consider ESG factors.

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Debt Securities Risks-The value of a debt security changes in response to various factors, including, for example, market-related factors, such as changes in interest rates or changes in the actual or perceived ability of an issuer to meet its obligations. Investments in debt securities are subject to, among other risks, credit risk, interest rate risk and high yield securities ("junk bond") risk, as described below.

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Credit Risks-An issuer or counterparty may fail to pay its obligations to the Fund when they are due. Financial strength and solvency (or the perceived financial strength or solvency) of an issuer are the primary factors influencing credit risk. Changes in the financial condition of an issuer or counterparty, changes in specific economic, social or political conditions that affect a particular type of security or other instrument or an issuer, and changes in economic, social or political conditions generally can increase the risk of default by an issuer or counterparty, which can affect a security's or other instrument's credit quality or value and an issuer's or counterparty's ability to pay interest and principal when due. The values of lower quality debt, including loans, tend to be particularly sensitive to these changes.

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High Yield Securities ("Junk Bond") Risks-Fixed income instruments rated below investment grade, or unrated securities that are determined by Artisan Partners to be of comparable quality, are high yield, high risk bonds, commonly known as "junk bonds."  These bonds are predominantly speculative. They are usually issued by companies without long track records of sales and earnings, or by companies with questionable credit strength. These bonds have a higher degree of default risk and may be less liquid than higher-rated bonds. These securities may be subject to greater price volatility due to such factors as specific corporate developments, interest rate sensitivity, negative perceptions of junk bonds generally and less secondary market liquidity. This potential lack of liquidity may make it more difficult for the Fund to accurately value these securities.

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Interest Rate Risks-Interest rate risk is the risk that fixed income securities and other instruments in the Fund's portfolio will fluctuate in value because of changes, or the anticipation of changes, in interest rates. In particular, during periods of rising interest rates, the values of such securities may decline and may result in losses to the Fund. Factors including central bank monetary policy, rising inflation rates, and changes in general economic conditions may cause interest rates to rise, which could cause the value of the Fund's investments to decline. Interest rate changes can be sudden and unpredictable, and the Fund may experience losses as a result of movements in interest rates. The Fund may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile in response to changing interest rates.

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Loan Risks-Investments in loans, including floating or adjustable rate loans, are generally subject to the same risks as investments in other types of debt obligations, including, among others, the credit risk of nonpayment of principal and interest. In addition, in many cases loans are subject to the risks associated with below investment grade securities. The Fund may invest in loans made in connection with highly leveraged transactions, which are subject to greater credit and liquidity risks than other types of loans. Although the loans in which the Fund invests may be secured by specific collateral, there can be no assurance that liquidation of such collateral would satisfy the borrower's obligation in the event of nonpayment of scheduled interest or principal, or that such collateral could be readily liquidated. In the event of the bankruptcy of a borrower, the Fund could experience delays or limitations with respect to its ability to realize the benefits of the collateral securing a loan or could recover nothing of what it is owed on the loan. Uncollateralized (i.e., non-secured) loans are subject to greater risk of loss (i.e., nonpayment) in the event of default than secured loans since they do not afford the Fund recourse to collateral. Investments in loans may be difficult to value and may be illiquid, including due to legal or contractual restrictions on resale. Transactions in many loans settle on a delayed basis, and the Fund may not receive the proceeds from the sale of a loan for a substantial period after the sale. As a result, sale proceeds related to the sale of loans may not be available to make additional investments or meet redemption obligations until a substantial period after the sale of the loans.

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Liquidity Risks-Liquidity risk is the risk that the Fund may be unable to sell a portfolio investment at a desirable time or at the value the Fund has placed on the investment. It may be more difficult for the Fund to determine a fair value of an illiquid investment than that of a more liquid comparable investment.

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Valuation Risks-The Fund's investments are valued in accordance with Artisan Partners' valuation policies. The valuation of any investment involves inherent uncertainty. The value of a security determined in accordance with the valuation policies may differ materially from the value that could have been realized in an actual sale or transfer for a variety of reasons, including the timing of the transaction and liquidity in the market.

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Stressed and Distressed Instruments Risks-Investments in the securities of financially stressed or distressed issuers involve substantial risks, including the risk that all or a portion of principal will not be repaid. These securities may present a substantial risk of default or may be in default at the time of investment. The Fund may incur additional expenses to the extent it is required to seek recovery upon a default in the payment of principal or interest on its portfolio holdings. As with any issuer, the team's judgments about the credit quality of a financially stressed or distressed issuer and the relative value of its securities may prove to be wrong.

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Futures Contract Risks-The Fund may enter into futures contracts, in which the Fund agrees to buy or sell a security or other asset on a specified future date at a specified price or rate. There are risks associated with futures contracts, including that the success of such an investment strategy may depend on an ability to predict movements in the prices of individual securities, fluctuations in markets and movements in interest rates; there may be an imperfect or no correlation between the changes in market value of the securities held by the Fund and the prices of futures; there may not be a liquid secondary market for a futures contract; trading restrictions or limitations may be imposed by an exchange; and government regulations may restrict trading in futures contracts.

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Counterparty Risks-The Fund will be subject to credit risk with respect to the counterparties to the derivative contracts and other instruments entered into by the Fund. If a counterparty becomes bankrupt or insolvent or otherwise fails to perform its obligations to the Fund due to financial difficulties, the Fund may experience significant losses or delays in obtaining any recovery (including recovery of any collateral it has provided to the counterparty) from the counterparty.

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Foreign Investing Risks-Foreign securities may underperform US securities and may be more volatile than US securities. Risks relating to investments in foreign securities and to securities of issuers with significant exposure to foreign markets include currency exchange rate fluctuation; less available public information about the issuers of securities; less stringent regulatory standards; lack of uniform accounting, auditing and financial reporting standards; and country risks, including less liquidity, high inflation rates, unfavorable economic practices, political instability and expropriation and nationalization risks.

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Emerging and Developing Markets Risks-Investment risks typically are greater in emerging and less developed markets, including "frontier markets", which are a subset of emerging markets and less developed markets that, generally, have smaller economies and less mature capital markets. For example, in addition to the risks associated with investments in any foreign country, political, legal and economic structures in these less developed countries may be new and changing rapidly, which may cause instability and greater risk of loss. Their securities markets may be less developed, and securities in those markets are generally more volatile and less liquid than those in the developed markets. Investing in emerging market countries may involve substantial risk due to, among other reasons, limited information; higher brokerage costs; different accounting, auditing and financial reporting standards; less developed legal systems and thinner trading markets as compared to those in developed countries; different clearing and settlement procedures and custodial services; and currency blockages or transfer restrictions. Emerging market countries also are more likely to experience high levels of inflation, deflation or currency devaluations, which could hurt their economies and securities markets. Certain emerging markets also may face other significant internal or external risks, including a heightened risk of war or ethnic, religious or racial conflicts. In addition, governments in many emerging market countries participate to a significant degree in their economies and securities markets, which may impair investment and economic growth of companies in those markets. Such markets may also be heavily reliant on foreign capital and, therefore, vulnerable to capital flight. Such risks may be greater in frontier markets.

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Currency Risks-Foreign securities usually are denominated and traded in foreign currencies and the exchange rates between foreign currencies and the US dollar fluctuate continuously. The Fund's performance will be affected by its direct or indirect exposure to a particular currency due to favorable or unfavorable changes in currency exchange rates relative to the US dollar. The Fund's direct or indirect exposure to a particular currency may be hedged to mitigate currency volatility or because the Fund believes a currency is overvalued. There can be no guarantee that any hedging activity will be successful. Hedging activity and/or use of forward foreign currency contracts may reduce or limit the opportunity for gain and involves counterparty risk, which is the risk that the contracting party will not fulfill its contractual obligation to deliver the currency contracted for at the agreed upon price to the Fund.

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Private Placement and Restricted Securities Risks-In addition to the general risks to which all securities are subject, securities acquired in a private placement generally are subject to strict restrictions on resale, and there may be no liquid secondary market or ready purchaser for such securities, and a liquid secondary market may never develop. Therefore, the Fund may be unable to dispose of such securities when it desires to do so or at a favorable time or price. This potential lack of liquidity may make it more difficult for the Fund to accurately value these securities. Issuers of private placements or other restricted securities may include special purpose vehicles ("SPVs") that hold underlying assets to which the Fund wants to gain exposure. The Fund may have the right to receive payments only from the SPV, and may not have direct rights against the issuer of the underlying assets. Investors in such SPVs generally pay their share of the SPV's administrative and other expenses, including management fees.

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Leverage Risks-Certain transactions, including, for example, the use of certain derivatives and borrowing money, can result in leverage. Leverage generally has the effect of increasing the amounts of loss or gain the Fund might realize and creates the likelihood of greater volatility of the value of the Fund's investments. There is risk of loss in excess of invested capital.

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Risks of Emphasizing a Region, Country, Sector or Industry-If the Fund has invested a higher percentage of its total assets in a particular region, country, sector or industry, changes affecting that region, country, sector or industry may have a significant impact on the performance of the Fund's overall portfolio.

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Impact of Actions by Other Shareholders-The Fund, like all mutual funds, pools the investments of many investors. Actions by one investor or multiple investors in the Fund may have an adverse effect on the Fund and on other investors. For example, shareholder purchase and redemption activity may affect the per share amount of the Fund's distributions of its net income and net realized gains, if any, thereby increasing or reducing the tax burden on the Fund's shareholders subject to income tax who receive Fund distributions.

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Operational and Cybersecurity Risks-Operational failures, cyber-attacks or other disruptions that affect the Fund's service providers, the Fund's counterparties, other market participants or the issuers of securities held by the Fund may adversely affect the Fund and its shareholders, including by causing losses for the Fund or impairing Fund operations.