Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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
OMB APPROVAL
OMB Number: 3235-0287
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
GUARINO CARL
  2. Issuer Name and Ticker or Trading Symbol
SEI INVESTMENTS CO [SEIC]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Executive Vice President
(Last)
(First)
(Middle)
ONE FREEDOM VALLEY DRIVE
3. Date of Earliest Transaction (Month/Day/Year)
04/25/2006
(Street)

OAKS, PA 19456
4. If Amendment, Date Original Filed(Month/Day/Year)
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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 03/02/2006   G V 20,000 D $ 0 (1) 218,937.9455 (2) D  
Common Stock               800 I For the benefit of the minor children (3)
Common Stock               50,328 I By the Carl and Alice Guarino 2004 Irrevocable Trust for Descendants (4)
Common Stock               173,963 I By the Carl A. Guarino 2004 Grantor Retained Annuity Trust
Common Stock 04/25/2006   M   90,000 A $ 7 308,937.9455 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Common Stock $ 7 04/25/2006   M     90,000 12/08/2004 05/01/2006(5) Common Stock 90,000 $ 7 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
GUARINO CARL
ONE FREEDOM VALLEY DRIVE
OAKS, PA 19456
      Executive Vice President  

Signatures

 Ruth A. Montgomery (Attorney-in-fact)   04/27/2006
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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) Not applicable - Gift Transfer
(2) No transactions occurred in 2005. Holdings represent a increase of 2.28 shares due to dividend reinvestment in the Employee Stock Purchase Plan.
(3) The reporting person disclaims ownership of all securities held in custodianship for the benefit of his minor children and the report should not be deemed as an admission that the reporting person is the beneficial owner of such securities for Section 16 or for any other purpose.
(4) The Carl & Alice Guarino 2004 Irrevocable Trust for Descendants (the "2004 Family Trust") was established in December 2004 for the benefit of Mr. Guarino's children and Mr. Guarino's sister-in-law is the Trustee.. The holdings reflect the transfer of 50,328 shares from Mr. Guarino's direct holdings to the 2004 Family Trust.
(5) The option vests upon the earlier of the Issuer's attainment of specific levels of earnings per share or seven years from the date of the grant. The options were set to expire on the ten year anniversary of the date of the grant. However, upon Mr. Guarino's resignation from his position as an Executive Vice President of SEI Investments Company effective March 31, 2006, all of his options immediately vested and will expire 30 days from the date of his resignation.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.