Rule 497 (k)
                                                             File No. 333-140895

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                                                                     AlphaDEX(R)
First Trust Technology AlphaDEX(R) Fund                           Family of ETFs
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SUMMARY PROSPECTUS: March 18, 2016      TICKER: FXL    EXCHANGE: NYSE Arca, Inc.
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Before you invest, you may want to review the Fund's prospectus, which contains
more information about the Fund and its risks. You can find the Fund's
prospectus and other information about the Fund, including the statement of
additional information and most recent reports to shareholders, online at
http://www.ftportfolios.com/retail/ETF/ETFfundnews.aspx?Ticker=FXL. You can also
get this information at no cost by calling (800) 621-1675 or by sending an
e-mail request to info@ftportfolios.com. The Fund's prospectus and statement of
additional information, both dated December 1, 2015, as supplemented on March
18, 2016, are all incorporated by reference into this Summary Prospectus.

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INVESTMENT OBJECTIVE

The First Trust Technology AlphaDEX(R) Fund (the "Fund") seeks investment
results that correspond generally to the price and yield (before the Fund's fees
and expenses) of an equity index called the StrataQuant(R) Technology Index (the
"Index").

FEES AND EXPENSES OF THE FUND

The following table describes the fees and expenses you may pay if you buy and
hold shares of the Fund. Investors purchasing and selling shares may be subject
to costs (including customary brokerage commissions) charged by their broker,
which are not reflected in the table below.

 SHAREHOLDER FEES (fees paid directly from your investment)
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 Maximum Sales Charge (Load) Imposed on Purchases
   (as a percentage of offering price)                                      None
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 ANNUAL FUND OPERATING EXPENSES (expenses that you pay each
   year as a percentage of the value of your investment)
      Management Fees                                                      0.50%
      Distribution and Service (12b-1) Fees(1)                             0.00%
      Fees Previously Waived or Expenses Reimbursed by First Trust(2)      0.00%
      Other Expenses                                                       0.13%
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      Total Annual Fund Operating Expenses                                 0.63%
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      Fee Waiver and Expense Reimbursement(2)                              0.00%
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      Total Net Annual Fund Operating Expenses After Fee Waiver
         and Expense Reimbursement                                         0.63%
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  (1) Although the Fund has adopted a 12b-1 plan that permits it to pay up to
      0.25% per annum, it will not pay 12b-1 fees any time before December 31,
      2016.

  (2) First Trust Advisors L.P., the Fund's investment advisor, has agreed to
      waive fees and/or reimburse Fund expenses to the extent that the operating
      expenses of the Fund (excluding interest expense, brokerage commissions
      and other trading expenses, taxes and extraordinary expenses) exceed 0.70%
      of its average daily net assets per year (the "Expense Cap") at least
      through November 30, 2016. Expenses reimbursed and fees waived under such
      agreement are subject to recovery by the Fund's investment advisor for up
      to three years from the date the fee was waived or expense was incurred,
      but no reimbursement payment will be made by the Fund if it results in the
      Fund exceeding an expense ratio equal to the Expense Cap in place at the
      time the expenses were reimbursed or fees waived by the Fund's investment
      advisor. The agreement may be terminated by the Trust on behalf of the
      Fund at any time and by the Fund's investment advisor only after November
      30, 2016 upon 60 days' written notice.


                                                                     FIRST TRUST
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EXAMPLE

The example below is intended to help you compare the cost of investing in the
Fund with the cost of investing in other funds. This example does not take into
account customary brokerage commissions that you pay when purchasing or selling
shares of the Fund in the secondary market.

The example assumes that you invest $10,000 in the Fund for the time periods
indicated. The example also assumes that your investment has a 5% return each
year and that the Fund's operating expenses remain at current levels.
Additionally, the example assumes that the Fund imposes a 12b-1 fee of 0.25% per
annum of the Fund's average daily net assets following December 31, 2016.
Although your actual costs may be higher or lower, based on these assumptions
your costs would be:

     1 YEAR             3 YEARS              5 YEARS              10 YEARS
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      $64                $253                 $461                 $1,059
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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
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 91%
of the average value of its portfolio.

PRINCIPAL INVESTMENT STRATEGIES

The Fund will normally invest at least 90% of its net assets (including
investment borrowings) in common stocks that comprise the Index. The Fund, using
an "indexing" investment approach, attempts to replicate, before fees and
expenses, the performance of the Index. The Fund's investment advisor seeks a
correlation of 0.95 or better (before fees and expenses) between the Fund's
performance and the performance of the Index; a figure of 1.00 would represent
perfect correlation.

The Index is in the "StrataQuant(R) Series," a family of custom enhanced indices
developed, maintained and sponsored by NYSE Group, Inc. or its affiliates
("NYSE" or an "Index Provider"), and licensed to First Trust Portfolios L.P. by
NYSE. Prior to the acquisition of the American Stock Exchange LLC (the "AMEX")
by NYSE, the equity indices in the StrataQuant(R) Series were developed,
maintained and sponsored by the AMEX. The Index is a modified equal-dollar
weighted index designed by NYSE to objectively identify and select stocks from
the Russell 1000(R) Index in the technology sector that may generate positive
alpha relative to traditional passive-style indices through the use of the
AlphaDEX(R) selection methodology. Alpha is an indication of how much an
investment outperforms or underperforms on a risk-adjusted basis relative to its
benchmark. As of July 31, 2015, the Index was comprised of 85 stocks. The Index
is rebalanced and reconstituted as of the last business day of each calendar
quarter. Changes to the Index will be effective at the open of trading on the
fourth business day of the following month.

PRINCIPAL RISKS

You could lose money by investing in the Fund. An investment in the Fund is not
a deposit of a bank and is not insured or guaranteed by the Federal Deposit
Insurance Corporation or any other governmental agency. There can be no
assurance that the Fund's investment objective will be achieved.

EQUITY SECURITIES RISK. Because the Fund invests in equity securities, the value
of the Fund's shares will fluctuate with changes in the value of these equity
securities. Equity securities prices fluctuate for several reasons, including
changes in investors' perceptions of the financial condition of an issuer or the
general condition of the relevant stock market, such as market volatility, or
when political or economic events affecting the issuers occur. In addition,
common stock prices may be particularly sensitive to rising interest rates, as
the cost of capital rises and borrowing costs increase.

GROWTH STOCKS INVESTMENT RISK. Growth stocks tend to be more volatile than
certain other types of stocks and their prices usually fluctuate more
dramatically than the overall stock market. A stock with growth characteristics
can have sharp price declines due to decreases in current or expected earnings.

INFORMATION TECHNOLOGY COMPANIES RISK. Information technology companies are
generally subject to the risks of rapidly changing technologies, short product
life cycles, fierce competition, aggressive pricing and reduced profit margins,
loss of patent, copyright and trademark protections, cyclical market patterns,
evolving industry standards, and frequent new product introductions. Information
technology companies may be smaller and less experienced companies, with limited
product lines, markets or financial resources and fewer experienced management
or marketing personnel. Information technology company stocks, particularly
those involved with the Internet, have experienced extreme price and volume
fluctuations that often have been unrelated to their operating performance.

MARKET RISK. Market risk is the risk that a particular security owned by the
Fund or shares of the Fund in general may fall in value. Securities are subject
to market fluctuations caused by such factors as economic, political, regulatory
or market developments, changes in interest rates and perceived trends in
securities prices. Shares of the Fund could decline in value or underperform
other investments.

NON-CORRELATION RISK. The Fund's return may not match the return of the Index
for a number of reasons. For example, the Fund incurs operating expenses not
applicable to the Index, and may incur costs in buying and selling securities,
especially when rebalancing the Fund's portfolio holdings to reflect changes in
the composition of the Index. In addition, the Fund's portfolio holdings may not
exactly replicate the securities included in the Index or the ratios between the
securities included in the Index.





REPLICATION MANAGEMENT RISK. The Fund is exposed to additional market risk due
to its policy of investing principally in the securities included in the Index.
As a result of this policy, securities held by the Fund will generally not be
bought or sold in response to market fluctuations.

SMALLER COMPANIES RISK. Small and/or mid-capitalization companies may be more
vulnerable to adverse general market or economic developments, and their
securities may be less liquid and may experience greater price volatility than
larger, more established companies as a result of several factors, including
limited trading volumes, products or financial resources, management
inexperience and less publicly available information. Accordingly, such
companies are generally subject to greater market risk than larger, more
established companies.

VALUE STOCKS INVESTMENT RISK. The intrinsic value of a stock with value
characteristics may not be fully recognized by the market for a long time or a
stock judged to be undervalued may actually be appropriately priced at a low
level.

ANNUAL TOTAL RETURN

The bar chart and table below illustrate the annual calendar year returns of the
Fund based on net asset value as well as the average annual Fund and Index
returns. The bar chart and table provide an indication of the risks of investing
in the Fund by showing changes in the Fund's performance from year-to-year and
by showing how the Fund's average annual total returns based on net asset value
compare to those of the Index, a broad-based market index and two specialized
securities market indices. With respect to the Russell 1000(R) Technology Index,
on or about September 18, 2008, Russell Investment Group ("Russell") began
calculating its Russell U.S. Indices using an enhanced Russell sector scheme,
the Russell Global Sectors (the "RGS"). The RGS and the former U.S. sector
scheme ran in tandem until June 30, 2009, when Russell officially transitioned
to the RGS and ceased calculating its indices using the U.S. sector scheme.
Consequently, performance data is not available for the Russell 1000(R)
Technology Index for the entire "Since Inception" period set forth in the table
because performance data does not exist using solely the U.S. sector scheme or
alternatively, using solely the RGS. See "Total Return Information" for
additional performance information regarding the Fund. The Fund's performance
information is accessible on the Fund's website at www.ftportfolios.com.

Returns before taxes do not reflect the effects of any income or capital gains
taxes. All after-tax returns are calculated using the historical highest
individual federal marginal income tax rates and do not reflect the impact of
any state or local tax. Returns after taxes on distributions reflect the taxed
return on the payment of dividends and capital gains. Returns after taxes on
distributions and sale of shares assume you sold your shares at period end, and,
therefore, are also adjusted for any capital gains or losses incurred. Returns
for the market indices do not include expenses, which are deducted from Fund
returns, or taxes.

Your own actual after-tax returns will depend on your specific tax situation and
may differ from what is shown here. After-tax returns are not relevant to
investors who hold Fund shares in tax-deferred accounts such as individual
retirement accounts (IRAs) or employee-sponsored retirement plans.

FIRST TRUST TECHNOLOGY ALPHADEX(R) FUND--TOTAL RETURNS(1)

                               [GRAPHIC OMITTED]
                     [DATA POINTS REPRESENTED IN BAR CHART]

                    Calendar Year Total Returns as of 12/31

                              Year              %
                             ------         --------
                              2008          -48.07%
                              2009           66.95%
                              2010           26.41%
                              2011          -11.65%
                              2012            8.97%
                              2013           37.73%
                              2014           16.38%

(1)   The Fund's year-to-date return based on net asset value for the period
      12/31/2014 to 9/30/2015 was -8.05%.

During the period shown in the chart above:

               BEST QUARTER                               WORST QUARTER
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          22.85% (June 30, 2009)                   -28.69% (December 31, 2008)
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The Fund's past performance (before and after taxes) is not necessarily an
indication of how the Fund will perform in the future.





AVERAGE ANNUAL TOTAL RETURNS FOR THE PERIODS ENDED DECEMBER 31, 2014



                                                                                                                 SINCE INCEPTION
                                                                                         1 YEAR       5 YEARS      (5/8/2007)
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     Return Before Taxes                                                                  16.38%       14.30%         7.58%
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     Return After Taxes on Distributions                                                  16.05%       14.17%         7.50%
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     Return After Taxes on Distributions and Sale of Shares                                9.26%       11.44%         6.04%
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     StrataQuant(R) Technology Index
        (reflects no deduction for fees, expenses or taxes)                               17.18%       15.19%         8.49%
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     Russell 1000(R) Index
        (reflects no deduction for fees, expenses or taxes)                               13.24%       15.64%         6.62%
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     S&P 500(R) Information Technology Index
        (reflects no deduction for fees, expenses or taxes)                               20.12%       14.86%         9.45%
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     Russell 1000(R) Technology Index
        (reflects no deduction for fees, expenses or taxes)                               20.32%       14.15%           --
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MANAGEMENT

      INVESTMENT ADVISOR

      First Trust Advisors L.P. ("First Trust" or the "Advisor")

      PORTFOLIO MANAGERS

      The Fund's portfolio is managed by a team (the "Investment Committee")
      consisting of:

          o   Daniel J. Lindquist, Chairman of the Investment Committee and
              Managing Director of First Trust;

          o   Jon C. Erickson, Senior Vice President of First Trust;

          o   David G. McGarel, Chief Investment Officer and Managing Director
              of First Trust;

          o   Roger F. Testin, Senior Vice President of First Trust;

          o   Stan Ueland, Senior Vice President of First Trust; and

          o   Chris A. Peterson, Senior Vice President of First Trust.

      The Investment Committee members are primarily and jointly responsible for
      the day-to-day management of the Fund. Each Investment Committee member
      has served as a part of the portfolio management team of the Fund since
      2007, except for Chris A. Peterson, who has served as a member of the
      portfolio management team since 2016.

PURCHASE AND SALE OF FUND SHARES

The Fund issues and redeems shares on a continuous basis, at net asset value,
only in Creation Units consisting of 50,000 shares. The Fund's Creation Units
are generally issued and redeemed in-kind for securities in which the Fund
invests and, in certain circumstances, for cash, and only to and from
broker-dealers and large institutional investors that have entered into
participation agreements. Individual shares of the Fund may only be purchased
and sold on NYSE Arca through a broker-dealer. Shares of the Fund trade on NYSE
Arca at market prices rather than net asset value, which may cause the shares to
trade at a price greater than net asset value (premium) or less than net asset
value (discount).

TAX INFORMATION

The Fund's distributions are taxable and will generally be taxed as ordinary
income or capital gains. Distributions on shares held in a tax deferred account,
while not immediately taxable, will be subject to tax when the shares are no
longer held in a tax deferred account.

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), First Trust and First Trust Portfolios L.P., the
Fund's distributor, 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.


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