Exhibit 99.1

Investor Contact:                         Media Contact:

Nicole Vattimo                            Dana Grosser

SEI    SEI

+1 610-676-4385                        +1 610-676-2459

nvattimo@seic.com                         dgrosser@seic.com

Pages:        8

FOR IMMEDIATE RELEASE

SEI REPORTS FIRST-QUARTER 2015 FINANCIAL RESULTS

Income from Operations Increases 19 Percent

OAKS, Pa., April 22, 2015 -- SEI Investments Company (NASDAQ:SEIC) today announced financial results for the first-quarter 2015. Diluted earnings per share were $.50 in first-quarter 2015 compared to $.43 in first-quarter 2014. Diluted earnings per share for first-quarter 2015 and 2014 reflect pre-tax gains of $2.8 million, or $.01 per share, and $5.6 million, or $.02 per share, respectively, from the sale of SEI Asset Korea.

Consolidated Overview
(In thousands, except earnings per share)		For the Three Months Ended March 31,
		2015				2014				%
Revenues			$325,444				$302,386			8%
Net income		84,611				74,820				13%
Diluted earnings per share			$0.50				$0.43			16%

"Our results for the first quarter demonstrate the success we are having in growing our company, increasing profitability, and expanding our customer base," said Alfred P. West, Jr., SEI Chairman and CEO. "SEI's business model, our ability to execute, and the completeness of our offerings enable us to manage through the mixed nature of global markets.

"Across our company, we are investing in products and services that position us well for long-term, sustainable growth as we work to meet the evolving needs of our clients and markets."

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Summary of First-Quarter Results by Business Segment

(In thousands)		For the Three Months Ended March 31,
		2015				2014				%
Private Banks:
Revenues			$111,213				$105,179			6%
Expenses		99,256				100,190				(1)%
Operating Profit		11,957				4,989				140%
Gain on sale of subsidiary		2,791				5,582				NM
Interest income		180				—				NM
Total Profit		14,928				10,571				NM
Operating Margin (A)		11		%		5		%
Investment Advisors:
Revenues		74,015				66,424				11%
Expenses		39,059				34,577				13%
Operating Profit		34,956				31,847				10%
Operating Margin		47		%		48		%
Institutional Investors:
Revenues		73,548				68,657				7%
Expenses		35,211				34,095				3%
Operating Profit		38,337				34,562				11%
Operating Margin		52		%		50		%
Investment Managers:
Revenues		65,367				61,008				7%
Expenses		40,623				39,184				4%
Operating Profit		24,744				21,824				13%
Operating Margin		38		%		36		%
Investments in New Businesses:
Revenues		1,301				1,118				16%
Expenses		4,866				4,249				15%
Operating Loss		(3,565		)		(3,131		)		NM
Totals:
Revenues			$325,444				$302,386			8%
Expenses		219,015				212,295				3%
Corporate overhead expenses		13,359				11,699				14%
Income from operations			$93,070				$78,392			19%

(A) Percentages determined exclusive of gain on sale of subsidiary and interest income.

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First-Quarter Business Highlights:

•	Revenue growth was primarily driven by higher Asset management, administration, and distribution fees from market appreciation and improved cash flows from new and existing clients.

•	Our average assets under management, excluding LSV, increased $14.9 billion, or nine percent, to $172.5 billion in the first-quarter 2015, as compared to $157.6 billion during the first-quarter 2014 (see attached Average Asset Balances schedules for further details).

•	Our average assets under administration increased $48.7 billion, or 14 percent, to $384.7 billion in the first-quarter 2015, as compared to $336.0 billion during the first-quarter 2014 (see attached Average Asset Balances schedules for further details).

•	Revenue growth was also driven by increased Information processing and software servicing fees in our Private Banks segment. The increase was primarily attributable to higher fees from the growth in assets processed on the SEI Wealth PlatformSM and increased non-recurring professional services fees.

•	Sales events, net of client losses, during first-quarter 2015 totaled approximately $30.9 million and are expected to generate net annualized recurring revenues of approximately $23.6 million when contract values are fully realized.

•	Income from LSV increased $2.1 million, or seven percent, to $34.3 million in first-quarter 2015 as compared to $32.2 million in first-quarter 2014 due to an increase in assets under management and an increase in performance fees earned by LSV.

•	We recorded pre-tax gains of $2.8 million, or $.01 diluted earnings per share, and $5.6 million, or $.02 diluted earnings per share, from the sale of SEI AK in first-quarter 2015 and 2014, respectively.

•	Amortization expense related to capitalized software was $10.3 million during the first-quarter 2015 as compared to $9.2 million during the first-quarter 2014 due to continued enhancements to the SEI Wealth Platform.

•	Our effective tax rates were 35.4 percent in first-quarter 2015 and 35.9 percent in first-quarter 2014.

•	In first-quarter 2015, we repurchased 1.5 million shares of our common stock for $65.3 million.

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Earnings Conference Call

A conference call to review earnings is scheduled for 2 p.m. Eastern time on April 22, 2015. Investors may listen to the call at seic.com/investors. The call may also be accessed at many financial services websites, including Google Finance and Yahoo Finance. Investors may also listen to replays at these websites, or by telephone at (USA) 800-475-6701; (International) 320-365-3844, access code 358144.

About SEI

SEI (NASDAQ:SEIC) is a leading global provider of investment processing, investment management, and investment operations solutions that help corporations, financial institutions, financial advisors, and ultra-high-net-worth families create and manage wealth. As of March 31, 2015, through its subsidiaries and partnerships in which the company has a significant interest, SEI manages or administers $648 billion in mutual fund and pooled or separately managed assets, including $258 billion in assets under management and $390 billion in client assets under administration. For more information, visit seic.com.

Many of the statements in this release may be considered “forward looking statements” and include discussions about future operations, strategies and financial results. Forward-looking statements are based upon estimates and assumptions that involve risks and uncertainties, many of which are beyond our control or are subject to change. Although we believe our assumptions are reasonable, they could be inaccurate. Our actual future revenues and income could differ materially from our expected results. We have no obligation to publicly update or revise any forward-looking statements.

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SEI INVESTMENTS COMPANY

CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share data)

(Unaudited)

		For the Three Months Ended March 31,
		2015				2014
Asset management, admin. and distribution fees			$246,768				$225,071
Information processing and software servicing fees		70,653				69,178
Transaction–based and trade execution fees		8,023				8,137
Total revenues		325,444				302,386
Subadvisory, distribution and other asset mgmt costs		38,517				34,012
Software royalties and other information processing costs		7,509				8,553
Brokerage commissions		5,972				5,979
Compensation, benefits and other personnel		94,186				94,424
Stock-based compensation		3,750				2,823
Consulting, outsourcing and professional fees		35,628				34,933
Data processing and computer related		13,400				12,620
Facilities, supplies and other costs		17,059				15,852
Amortization		10,358				9,214
Depreciation		5,995				5,584
Total expenses		232,374				223,994
Income from operations		93,070				78,392
Net gain on investments		250				136
Interest and dividend income		969				777
Interest expense		(113		)		(113		)
Equity in earnings of unconsolidated affiliates		34,033				31,891
Gain on sale of subsidiary		2,791				5,582
Income before income taxes		131,000				116,665
Income taxes		46,389				41,845
Net income		84,611				74,820
Basic earnings per common share			$0.51				$0.44
Shares used to calculate basic earnings per share		166,695				169,306
Diluted earnings per common share			$0.50				$0.43
Shares used to calculate diluted earnings per share		170,703				173,828

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SEI INVESTMENTS COMPANY

BALANCE SHEETS

(In thousands)

(Unaudited)

		March 31,				December 31,
		2015				2014
Assets
Current Assets:
Cash and cash equivalents			$643,260				$667,446
Restricted cash		5,805				5,801
Receivables from regulated investment companies		47,006				48,393
Receivables, net		200,673				194,419
Securities owned		21,192				21,175
Other current assets		25,028				18,193
Total Current Assets		942,964				955,427
Property and Equipment, net		125,855				125,535
Capitalized software, net		306,728				309,040
Investments available for sale		74,222				77,609
Investments in affiliated funds, at fair value		4,454				4,523
Investment in unconsolidated affiliates		51,320				54,290
Other assets, net		16,442				16,451
Total Assets			$1,521,985				$1,542,875
Liabilities and Equity
Current Liabilities:
Accounts payable			$6,050				$10,588
Accrued liabilities		152,227				207,429
Deferred income taxes, net		1,298				1,414
Deferred revenue		3,618				1,749
Total Current Liabilities		163,193				221,180
Deferred income taxes		63,742				63,755
Other long-term liabilities		10,791				10,327
Total Liabilities		237,726				295,262
Shareholders' Equity:
Common stock		1,661				1,667
Capital in excess of par value		854,995				834,615
Retained earnings		445,368				420,226
Accumulated other comprehensive loss, net		(17,765		)		(8,895		)
Total Shareholders' Equity		1,284,259				1,247,613
Total Liabilities and Shareholders' Equity			$1,521,985				$1,542,875

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SEI INVESTMENTS COMPANY

ENDING ASSET BALANCES

(In millions)

(Unaudited)

			Mar. 31,				Jun. 30,				Sept. 30,				Dec 31,				Mar. 31,
			2014				2014				2014				2014				2015
Private Banks:
Equity/Fixed Income programs				$16,918				$18,679				$18,634				$18,666				$19,296
Collective Trust Fund programs			14				12				11				8				9
Liquidity funds			5,670				5,274				5,331				5,889				5,551
Total assets under management				$22,602				$23,965				$23,976				$24,563				$24,856
Client assets under administration			15,641				15,347				16,288				16,741				17,643
Total assets				$38,243				$39,312				$40,264				$41,304				$42,499
Investment Advisors:
Equity/Fixed Income programs				$39,981				$42,125				$42,260				$43,845				$45,800
Collective Trust Fund programs			13				13				9				9				8
Liquidity funds			2,802				2,696				3,086				3,173				3,047
Total assets under management				$42,796				$44,834				$45,355				$47,027				$48,855
Institutional Investors:
Equity/Fixed Income programs				$69,194				$71,598				$72,006				$72,828				$74,178
Collective Trust Fund programs			102				100				98				95				94
Liquidity funds			2,505				2,414				2,891				2,929				3,246
Total assets under management				$71,801				$74,112				$74,995				$75,852				$77,518
Investment Managers:
Equity/Fixed Income programs				$68				$64				$64				$27				$25
Collective Trust Fund programs			22,633				22,598				21,297				20,833				20,965
Liquidity funds			782				802				1,018				946				1,091
Total assets under management				$23,483				$23,464				$22,379				$21,806				$22,081
Client assets under administration (A)			326,735				337,492				346,841				355,890				372,116
Total assets				$350,218				$360,956				$369,220				$377,696				$394,197
Investments in New Businesses:
Equity/Fixed Income programs				$632				$659				$703				$736				$756
Liquidity funds			49				38				118				98				106
Total assets under management				$681				$697				$821				$834				$862
LSV Asset Management:
Equity/Fixed Income programs				$77,973				$82,026				$81,536				$82,665				$84,123
Total:
Equity/Fixed Income programs (B)				$204,766				$215,151				$215,203				$218,767				$224,178
Collective Trust Fund programs			22,762				22,723				21,415				20,945				21,076
Liquidity funds			11,808				11,224				12,444				13,035				13,041
Total assets under management				$239,336				$249,098				$249,062				$252,747				$258,295
Client assets under administration (C)			342,376				352,839				363,129				372,631				389,759
Total assets				$581,712				$601,937				$612,191				$625,378				$648,054

(A)	Client assets under administration in the Investment Managers segment include $48.9 billion of assets balances that require limited services and therefore are at fee levels below our normal full service assets (as of March 31, 2015).

(B)	Equity/Fixed Income programs include $5.3 billion of assets invested in various asset allocation funds at March 31, 2015.

(C)	In addition to the numbers presented, SEI also administers an additional $6.7 billion in Funds of Funds assets (as of

March 31, 2015) on which SEI does not earn an administration fee.

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SEI INVESTMENTS COMPANY

AVERAGE ASSET BALANCES

(In millions)

(Unaudited)

			1st Qtr.				2nd Qtr.				3rd Qtr.				4th Qtr.				1st Qtr.
			2014				2014				2014				2014				2015
Private Banks:
Equity/Fixed Income programs				$16,114				$17,829				$18,804				$18,606				$18,869
Collective Trust Fund programs			14				12				12				10				8
Liquidity funds			5,757				5,429				5,466				5,537				5,755
Total assets under management				$21,885				$23,270				$24,282				$24,153				$24,632
Client assets under administration			15,366				15,069				15,707				16,451				17,504
Total assets				$37,251				$38,339				$39,989				$40,604				$42,136
Investment Advisors:
Equity/Fixed Income programs				$39,005				$40,887				$42,389				$43,104				$44,809
Collective Trust Fund programs			13				13				11				9				9
Liquidity funds			2,806				2,637				2,830				3,087				3,072
Total assets under management				$41,824				$43,537				$45,230				$46,200				$47,890
Institutional Investors:
Equity/Fixed Income programs				$67,697				$70,706				$72,010				$72,771				$73,760
Collective Trust Fund programs			103				134				98				96				95
Liquidity funds			2,571				2,664				2,883				2,973				3,021
Total assets under management				$70,371				$73,504				$74,991				$75,840				$76,876
Investment Managers:
Equity/Fixed Income programs				$68				$68				$64				$64				$27
Collective Trust Fund programs			22,004				22,447				22,123				21,140				21,108
Liquidity funds			738				824				962				904				1,066
Total assets under management				$22,810				$23,339				$23,149				$22,108				$22,201
Client assets under administration			320,644				333,373				344,661				355,903				367,206
Total assets				$343,454				$356,712				$367,810				$378,011				$389,407
Investments in New Businesses:
Equity/Fixed Income programs				$623				$640				$688				$731				$755
Liquidity funds			46				43				139				97				101
Total assets under management				$669				$683				$827				$828				$856
LSV Asset Management:
Equity/Fixed Income programs				$76,306				$79,866				$82,402				$83,187				$83,439
Total:
Equity/Fixed Income programs				$199,813				$209,996				$216,357				$218,463				$221,659
Collective Trust Fund programs			22,134				22,606				22,244				21,255				21,220
Liquidity funds			11,918				11,597				12,280				12,598				13,015
Total assets under management				$233,865				$244,199				$250,881				$252,316				$255,894
Client assets under administration			336,010				348,442				360,368				372,354				384,710
Total assets				$569,875				$592,641				$611,249				$624,670				$640,604

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