Exhibit 99.1

PDI Reports $0.34 Diluted EPS in Second Quarter 2004

Second Quarter Revenue of $83.2 Million a 16.8% Increase Over Year Ago

        SADDLE RIVER, N.J., Aug. 9 /PRNewswire-FirstCall/ — PDI, Inc. (Nasdaq: PDII) a healthcare sales and marketing company, today announced its second quarter 2004 financial results.

        Second Quarter Results
        Net revenue for the quarter ended June 30, 2004 was $83.2 million, 16.8% higher than net revenue of $71.3 million for the quarter ended June 30, 2003. Operating income was $8.2 million for the quarter ended June 30, 2004, compared to operating income of $4.5 million for the quarter ended June 30, 2003. Net income was $5.0 million for the quarter ended June 30, 2004, compared to net income of $2.8 million in the quarter ended June 30, 2003. Diluted net income per share for the quarter ended June 30, 2004 was $0.34 versus diluted net income per share of $0.20 for the quarter ended June 30, 2003.

        Year-to-Date Results
        Net total revenue for the six months ended June 30, 2004 was $171.6 million, 23.6% higher than total net revenue of $138.8 million for the six months ended June 30, 2003. Operating income was $18.0 million for the six months ended June 30, 2004 versus operating income of $5.6 million for the six months ended June 30, 2003. Net income was $11.0 million for the six months ended June 30, 2004 versus net income of $3.6 million for the six months ended June 30, 2003. Diluted net income per share was $0.74 for the six months ended June 30, 2004 compared to diluted net income per share of $0.25 for the six months ended June 30, 2003.

        Charles T. Saldarini, Vice Chairman and CEO, said, “Our strong performance in the second quarter is acceptable. More important is our view that the macro-level drivers of our business are favorable and we feel energized to execute our growth strategy.”

        Webcast Conference Call
        PDI will conduct a live webcast of its Earnings Release Briefing at 9:00 AM EDT on Tuesday, August 10, 2004. The live webcast of the event will be accessible through PDI’s website, http://www.pdi-inc.com and will be archived on the website for future on-demand replay. For those without internet access, the call can be accessed by dialing 1-877-423-4030 within the US and 1-706-634-1929 internationally and asking for the PDI Earnings Release Conference Call. The call will be archived for two weeks and can be accessed by calling 1-800-642-1687 or 1-706-645-9291 and entering the conference ID number 8680828.

        About PDI
        PDI, a premier healthcare sales and marketing company, provides strategic alternatives to the portfolio challenges of biopharmaceutical and medical device and diagnostics manufacturers. Focusing on two core businesses, sales and marketing services and product commercialization, PDI leverages its expertise and commercial infrastructure to maximize profitable brand growth. Manufacturers choose the relationship which best meets their strategic and financial objectives, ranging from individual or bundled service agreements to broader commercial partnerships. For more information, visit the Company’s website at http://www.pdi-inc.com.

        Forward Looking Statement
        This press release contains forward-looking statements regarding future events and financial performance. These statements involve a number of risks and uncertainties and are based on numerous assumptions involving judgments with respect to future economic, competitive and market conditions and future business decisions, all of which are difficult or impossible to predict accurately and many of which are beyond PDI’s control. Some of the important factors that could cause actual results to differ materially from those indicated by the forward-looking statements are general economic conditions, changes in our operating expenses, adverse patent rulings, FDA or legal developments, competitive pressures, failure to meet performance benchmarks in significant contracts, changes in customer and market requirements and standards, and the risk factors detailed from time to time in PDI’s periodic filings with the Securities and Exchange Commission, including without limitation, PDI’s Annual Report on Form 10-K for the year ended December 31, 2003, and PDI’s periodic reports on Forms 10-Q and 8-K filed with the Securities and Exchange Commission since January 1, 2004. The forward looking-statements in this press release are based upon management’s reasonable belief as of the date hereof. PDI undertakes no obligation to revise or update publicly any forward-looking statements for any reason.

PDI, INC.
CONSOLIDATED BALANCE SHEETS
(in thousands, except share data)
(unaudited)

June 30, December 31,
2004 2003
ASSETS      
Current assets:  
  Cash and cash equivalents   $   91,545   $ 113,288  
  Short-term investments   33,795   1,344  
  Inventory, net   —   43  
  Accounts receivable, net of allowance for  
   doubtful accounts of $559 and $749 as of  
   June 30, 2004 and December 31, 2003,  
   respectively   30,848   40,885  
  Unbilled costs and accrued profits on  
   contracts in progress   4,991   4,041  
  Deferred training and other program costs   3,037   1,643  
  Other current assets   11,831   8,847  
  Deferred tax asset   6,834   11,053  
Total current assets   182,881   181,144  
           
Net property and equipment   16,892   14,494  
Deferred tax asset   7,304   7,304  
Goodwill   11,132   11,132  
Other intangible assets   1,341   1,648  
Other long-term assets   3,830   3,901  
Total assets   $ 223,380   $ 219,623  
           
         LIABILITIES AND STOCKHOLDERS’ EQUITY  
Current liabilities:  
  Accounts payable   $     5,162   $     8,689  
  Accrued returns   11,382   22,811  
  Accrued incentives   14,050   20,486  
  Accrued salaries and wages   9,203   9,031  
  Unearned contract revenue   15,397   3,604  
  Restructuring accruals   444   744  
  Income taxes and other accrued expenses   14,294   15,770  
Total current liabilities   69,932   81,135  
Total long-term liabilities   —   —  
Total liabilities   $   69,932   $   81,135  
           
Commitments and Contingencies  
   
Stockholders’ equity:  
  Common stock, $.01 par value, 100,000,000  
   shares authorized: shares issued and  
   outstanding, June 30, 2004 - 14,619,271,  
   and December 31, 2003 - 14,387,126;  
   161,115 and 136,178 restricted shares  
   issued and outstanding at June 30, 2004  
   and December 31, 2003, respectively   $        148   $        145  
  Preferred stock, $.01 par value, 5,000,000  
   shares authorized, no shares issued and  
   outstanding   —   —  
Additional paid-in capital (includes restricted  
 of $4,955 and $2,361 as of June 30, 2004 and  
 December 31, 2003, respectively)   115,421   109,531  
Retained earnings   40,523   29,505  
Accumulated other comprehensive income   58   25  
Unamortized compensation costs   (2,592 ) (608 )
Treasury stock, at cost: 5,000 shares   (110 ) (110 )
Total stockholders’ equity   $ 153,448   $ 138,488  
Total liabilities & stockholders’ equity   $ 223,380   $ 219,623  

PDI, INC.
CONSOLIDATED STATEMENTS OF OPERATIONS
(in thousands, except per share data)
(unaudited)

                        Three Months Ended June 30   Six Months Ended June 30,  
    2004   2003   2004   2003  
Revenue  
  Service, net   $ 84,334   $71,177   $ 172,600   $ 138,688  
  Product, net   (1,131 ) 82   (1,030 ) 116  
     Total revenue, net   83,203   71,259   171,570   138,804  
Cost of goods and  
 services  
   Program expenses  
    (including related  
    party amounts of  
    $0 and $328 for  
    the quarters ended  
    June 30, 2004 and  
    2003, respectively  
    and $180 and $401  
    for the six months  
    ended June 30, 2004  
    and 2003,  
    respectively)   61,298   50,307   123,005   100,188  
   Cost of goods sold   89   83   233   145  
     Total cost of goods  
      and services   61,387   50,390   123,238   100,333  
                   
Gross profit   21,816   20,869   48,332   38,471  
Compensation expense   7,924   9,123   18,140   17,997  
Other selling, general  
 and administrative  
 expenses   5,657   7,206   12,148   13,039  
Restructuring and other  
 related expenses   —   —   —   (270 )
Litigation settlement   —   —   —   2,100  
    Total operating  
     expenses   13,581   16,329   30,288   32,866  
Operating income   8,235   4,540   18,044   5,605  
Other income, net   313   226   631   495  
Income before provision  
 for taxes   8,548   4,766   18,675   6,100  
Provision for income  
 taxes   3,505   1,954   7,657   2,510  
Net income   $   5,043   $  2,812   $   11,018   $     3,590  
                   
Basic net income per  
 share   $     0.35   $    0.20   $       0.76   $       0.25  
Diluted net income per  
 share   $     0.34   $    0.20   $       0.74   $       0.25  
                   
Basic weighted average  
 number of shares  
 outstanding   14,533   14,188   14,497   14,177  
Diluted weighted average  
 number of shares  
 outstanding   14,918   14,266   14,843   14,252  

SOURCE PDI, Inc.
           -0-          08/09/2004
           /CONTACT: Stephen P. Cotugno, Executive Vice President-Corporate Development of PDI, Inc., +1-201-574-8617/
           /Web site: http://www.pdi-inc.com /
           (PDII)

CO: PDI, Inc.
ST: New Jersey
IN: HEA BIO MTC ADV
SU: ERN CCA