Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Andreano Dominic J
 2. Date of Event Requiring Statement (Month/Day/Year)
05/10/2012		 3. Issuer Name and Ticker or Trading Symbol
MEDNAX, INC. [MD]
(Last)
(First)
(Middle)
1301 CONCORD TERRACE		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Sr.VP,General Counsel & Secy.
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SUNRISE, FL 33323		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 4,591.2698 (1) (2)
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Options (Right to Buy) 02/25/2007 02/25/2014 Common Stock 10,000 (3) $ 32.63 D  
Stock Options (Right to Buy) 06/01/2009 06/01/2016 Common Stock 4,063 (4) $ 44.7 D  
Stock Options (Right to Buy) 06/01/2010 06/01/2017 Common Stock 3,000 (5) $ 57.09 D  
Stock Options (Right to Buy) 06/02/2011 06/02/2018 Common Stock 3,000 (6) $ 55.43 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Andreano Dominic J
1301 CONCORD TERRACE
SUNRISE, FL 33323		       Sr.VP,General Counsel & Secy.  

Signatures

/s/ Dominic J. Andreano 05/11/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Includes 925 shares of restricted stock granted on June 1, 2009 pursuant to Issuer's 2008 Incentive Compensation Plan ("2008 ICP"), that will vest on June 1, 2012, 1,410 shares of restricted stock granted on June 1, 2010 pursuant to Issuer's 2008 ICP that will vest in equal installments on June 1, 2012 and June 1, 2013 and 1,596 shares of restricted stock granted on June 1, 2011 pursuant to the Issuer's 2008 ICP that will vest in three equal installments on June 1, 2012, June 1, 2013 and June 1, 2014.
(2) Includes 660.2698 shares acquired by the Reporting Person through the Issuer's Employee Stock Purchase Plan.
(3) Stock Options granted on May 7, 2004 pursuant to Issuer's 2004 Incentive Compensation Plan.
(4) Stock Options granted on June 1, 2006 pursuant to Issuer's 2004 Incentive Compensation Plan.
(5) Stock Options granted on June 1, 2007 pursuant to Issuer's 2004 Incentive Compensation Plan.
(6) Stock Options granted on June 2, 2008 pursuant to Issuer's 2008 Incentive Compensation Plan.

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