MARCH 1, 2011, as amended July 1, 2011

Summary Prospectus
Calamos Blue Chip Fund
NASDAQ Symbol: CBCAX – Class A  CBCBX – Class B  CBXCX– Class C

Before you invest, you may want to review the Fund’s prospectus and statement of additional information, which contain more information about the Fund and its risks. You can find the Fund’s prospectus, statement of additional information and other information about the Fund online at http://fundinvestor.calamos.com/FundLit. You can also get this information at no cost by calling 800.582.6959 or by sending an e-mail request to prospectus@calamos.com. The current prospectus and statement of additional information, both dated March 1, 2011 (and as each may be amended or supplemented), are incorporated by reference into this summary prospectus.

Investment Objective

Calamos Blue Chip Fund’s investment objective is long-term capital growth.

Fees and Expenses of the Fund

The following table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Calamos Funds. More information about these and other discounts is available from your financial professional and under “Fund Facts — What classes of shares do the Funds offer?” on page 76 of the Fund’s prospectus and “Share Classes and Pricing of Shares” on page 50 of the Fund’s statement of additional information.

Shareholder Fees (fees paid directly from your investment):
	CLASS A		CLASS B		CLASS C
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)		4.75%		None		None
Maximum Deferred Sales Charge (Load) (as a percentage of the lesser of the redemption price or offering price)		None		5.00%		1.00%
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
	CLASS A		CLASS B		CLASS C
Management Fees		1.00%		1.00%		1.00%
Distribution and/or Service Fees (12b-1)		0.25%		1.00%		1.00%
Other Expenses3		0.31%		0.31%		0.31%
Total Annual Operating Expenses		1.56%		2.31%		2.31%
Expense Reimbursement1		(0.41)%		(0.41)%		(0.41)%
Total Annual Operating Expenses After Reimbursement2		1.15%		1.90%		1.90%

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The Fund’s investment adviser has contractually agreed to reimburse Fund expenses through June 30, 2013 to the extent necessary so that Total Annual Fund Operating Expenses (excluding taxes, interest, short interest, short dividend expenses, brokerage commissions, acquired fund fees and expenses, and extraordinary expenses, if any) of Class A, Class B and Class C are limited to 1.15%, 1.90% and 1.90% of average net assets, respectively.

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The expenses in the table have been restated to reflect current fees. Actual expenses may vary.

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then either redeem or do not redeem your shares at the end of the reflected time periods. The example also assumes that your investment has a 5% return each year that all dividends and capital gain distributions are reinvested, that you pay a maximum initial or contingent deferred sales charge and that the Fund’s operating expenses remain the same (except for the ten-year amounts for Class B shares, which reflect the conversion of Class B shares to Class A shares in years nine and ten). Although your actual performance and costs may be higher or lower, based on these assumptions, your costs would be:

	REDEMPTION						NO REDEMPTION
	A		B		C		A		B		C
1 Year		587		693		293		587		193		193
3 Years		866		941		641		866		641		641
5 Years		1,209		1,359		1,159		1,209		1,159		1,159
10 Years		2,176		2,393		2,582		2,176		2,393		2,582

BCPRO 03/11

rev 07/1/11

Calamos Blue Chip Fund

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in the annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 49.4% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests primarily in equity securities issued by U.S. companies. Under normal market conditions, the Fund invests at least 80% of its net assets (plus any borrowings) in “Blue Chip” companies. For this purpose, a Blue Chip company is one whose stock is included in the Standard & Poor’s 500 Stock Index or the Dow Jones Industrial Average or a company with a market capitalization of at least $2 billion that the Fund’s investment adviser believes is well established, well known and financially viable (usually with at least four consecutive quarters of as-reported earnings, excluding discontinued operations and extraordinary items). The Fund may invest up to 25% of its net assets in foreign securities.

In pursuing its investment objective, the Fund seeks out a portfolio that opportunistically blends “Blue Chip” growth and value companies, with a bias toward companies that, in the investment adviser’s opinion, offer the best opportunities for growth. The Fund’s investment adviser typically considers the company’s financial soundness, earnings and cash flow forecast and quality of management. The Fund’s investment adviser seeks to lower the risks of investing in stocks by using a “top-down approach” of diversification by company, industry, sector, country and currency and focusing on macro-level investment themes.

Principal Risks

An investment in the Fund is subject to risks, and you could lose money on your investment in the Fund. There can be no assurance that the Fund will achieve its investment objective. The risks associated with an investment in the Fund can increase during times of significant market volatility. Your investment in the Fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The principal risks of investing in the Fund include:

•  Equity Securities Risk — The securities markets are volatile, and the market prices of the Fund’s securities may decline generally. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions. If the market prices of the securities owned by the Fund fall, the value of your investment in the Fund will decline.

•  Growth Stock Risk — Growth securities typically trade at higher multiples of current earnings than other securities and, therefore, may be more sensitive to changes in current or expected earnings than other equity securities and may be more volatile.

•  Value Stock Risk — Value stocks involve the risk that they may never reach what the underlying funds’ investment adviser believes is their full market value. Additionally, because different types of stocks tend to shift in and out of favor depending on market conditions, a value fund’s performance may sometimes be higher or lower than that of other types of funds (such as those emphasizing growth stocks).

•  Foreign Securities Risk — Risks associated with investing in foreign securities include fluctuations in the exchange rates of foreign currencies that may affect the U.S. dollar value of a security, the possibility of substantial price volatility as a result of political and economic instability in the foreign country, less public information about issuers of securities, different securities regulation, different accounting, auditing and financial reporting standards and less liquidity than in U.S. markets.

•  Portfolio Selection Risk — The value of your investment may decrease if the investment adviser’s judgment about the attractiveness, value or market trends affecting a particular security, issuer, industry or sector or about market movements is incorrect.

Performance

The following bar chart and table indicate the risks of investing in the Fund by showing changes in the Fund’s performance from calendar year to calendar year and how the Fund’s average annual total returns compare with those of a broad measure of market performance. All returns include the reinvestment of dividends and distributions. As always, please note that the Fund’s past performance (before and after taxes) cannot predict how it will perform in the future. Updated performance information is available at no cost by visiting www.calamos.com or by calling 800.582.6959.

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Calamos Blue Chip Fund

CLASS A ANNUAL TOTAL RETURN FOR YEARS ENDED 12.31

Best Quarter: 18.03% (6.30.09) Worst Quarter: -21.92% (12.31.08)

Average Annual Total Returns as of 12.31.10

The following table shows how the Fund’s average annual performance (before and after taxes) for the one-and five-year periods ended December 31, 2010 and since the Fund’s inception compared with broad measures of market performance. “Since Inception” returns shown for each index are returns since the inception of the Fund’s Class A shares, or since the nearest subsequent month end when comparative index data is available only for full monthly periods. The after-tax returns show the impact of assumed federal income taxes on an investment in the Fund. “Return After Taxes on Distributions” shows the effect of taxable distributions, but assumes that you still hold the Fund shares at the end of the period and so do not have any taxable gain or loss on your investment. “Return After Taxes on Distributions and Sale of Fund Shares” shows the effect of taxable distributions and any taxable gain or loss that would be realized if the Fund shares were purchased at the beginning and sold at the end of the specified period.

The after-tax returns are shown only for Class A shares, are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns for classes other than Class A will vary from returns shown for Class A.

AVERAGE ANNUAL TOTAL RETURNS AS OF 12.31.10
	INCEPTION								SINCE
	DATE OF CLASS		ONE YEAR			FIVE YEARS			INCEPTION
Calamos Blue Chip Fund — Class A		12.1.03
Return Before Taxes				7.86	%		2.14	%		3.81	%
Return After Taxes on Distributions				7.86	%		1.90	%		3.64	%
Return After Taxes on Distributions and Sale of Fund Shares				5.11	%		1.83	%		3.29	%
Calamos Blue Chip Fund — Class B		12.1.03
Return Before Taxes				7.36	%		1.98	%		3.74	%
Calamos Blue Chip Fund — Class C		12.1.03
Return Before Taxes				11.35	%		2.36	%		3.75	%
S&P 500 Index				15.06	%		2.29	%		4.39	%
Russell 1000® Growth Index				16.71	%		3.75	%		4.78	%

The Russell 1000 Growth Index measures the performance of those companies in the Russell 1000 Index with higher price-to-book ratios and higher forecasted growth values. The Russell 1000 Growth Index is provided to show how the Fund’s performance compares with the returns of an index of securities similar to those in which the Fund invests.

Investment Adviser

Calamos Advisors LLC

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Calamos Blue Chip Fund

PORTFOLIO MANAGER/ FUND TITLE (IF APPLICABLE)	PORTFOLIO MANAGER EXPERIENCE IN THE FUND	PRIMARY TITLE WITH INVESTMENT ADVISER
John P. Calamos, Sr. (President, Chairman)	since Fund’s inception	Chief Executive Officer, Co-CIO
Nick P. Calamos (Vice President)	since Fund’s inception	President of Investments, Co-CIO
John P. Calamos Jr.	since Fund’s inception	EVP
Jeff Scudieri	since Fund’s inception	SVP, Co-Head of Research and Investments
Jon Vacko	since Fund’s inception	SVP, Co-Head of Research and Investments
John Hillenbrand	since Fund’s inception	SVP, Senior Strategy Analyst
Steve Klouda	since Fund’s inception	SVP, Senior Strategy Analyst
Christopher Hartman	3 years	AVP, Senior Strategy Analyst
Joe Wysocki	3 years	AVP, Senior Strategy Analyst

Buying and Redeeming Fund Shares

Minimum Initial Investment: Class A and C: $2,500/$500 for IRA

Minimum Additional Investment: Classes A and C: $50

To Place Orders, please contact your intermediary, or place your order directly by mail: U.S. Bancorp Fund Services, LLC
P.O. Box 701
Milwaukee, WI 53201
Phone: 800.582.6959

Effective on July 31, 2009, the Fund no longer accepts purchases of Class B shares from new or existing investors, except from existing investors through the reinvestment of dividends and/or capital gain distributions in Class B shares of the same Fund or by exchange of existing Class B shares held in another Fund.

Transaction Policies

The Fund’s shares are redeemable. In general, investors may purchase, redeem, or exchange Fund shares on any business day by written request (to the address noted above), by wire transfer, by telephone (at the number noted above), or through a financial intermediary. Orders to buy and redeem shares are processed at the next net asset value (share price or “NAV”) to be calculated only on days when the New York Stock Exchange is open for regular trading.

Tax Information

The Fund’s distributions may be taxable as ordinary income or capital gains, except when your investment is in an IRA, 401(k) or other tax-advantaged investment plan.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

Click here to view the Fund’s statutory prospectus or statement of additional information.

2020 Calamos Court

Naperville, IL 60563-2787

800.582.6959

www.calamos.com

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