
| Neil Patrick Harris | ... | Douglas 'Doogie' Howser / ... (97 episodes, 1989-1993) |

| Max Casella | ... | Vinnie Delpino (91 episodes, 1989-1993) |
 | Lawrence Pressman | ... | Dr. Benjamin Canfield (90 episodes, 1989-1993) |
 | James Sikking | ... | Dr. David Howser (88 episodes, 1989-1993) |
 | Belinda Montgomery | ... | Katherine O'Brien Howser / ... (87 episodes, 1989-1993) |
 | Kathryn Layng | ... | Nurse Curly Spaulding (87 episodes, 1989-1993) |
 | Lucy Boryer | ... | Janine Stewart (61 episodes, 1989-1993) |
 | Markus Redmond | ... | Raymond Alexander (59 episodes, 1990-1993) |
 | Mitchell Anderson | ... | Dr. Jack McGuire (51 episodes, 1989-1991) |
 | Lisa Dean Ryan | ... | Wanda Plenn (48 episodes, 1989-1992) |

| Rif Hutton | ... | Dr. Ron Welch / ... (15 episodes, 1989-1993) |

| Robyn Lively | ... | Nurse Michele Faber (5 episodes, 1991-1993) |
 | Linda Klein | ... | Nurse Klein / ... (5 episodes, 1989-1992) |

| Carlease Burke | ... | Paramedic / ... (4 episodes, 1991-1993) |
 | Lainey Hashorva | ... | Nurse / ... (3 episodes, 1989-1990) |
 | Sami Chester | ... | Alvin / ... (3 episodes, 1989-1990) |

| David Selburg | ... | Dr. Michaels (3 episodes, 1989-1991) |
 | Huck Liggett | ... | Dr. Lucas (3 episodes, 1989) |

| Don Calfa | ... | Carmine Delpino (3 episodes, 1990-1993) |

| James Hong | ... | Gardener / ... (3 episodes, 1991-1992) |

| Peter Riga | ... | Orderly (3 episodes, 1991) |
 | Julian Christopher | ... | Dr. Cooper / ... (2 episodes, 1989) |

| Lee Wilkof | ... | Dr. Goring (2 episodes, 1989-1990) |
 | Eva Loseth | ... | Laura (2 episodes, 1992-1993) |
 | Ron Canada | ... | Officer Wilbur (2 episodes, 1992) |
 | Bill Hudson | ... | Michael Plenn (2 episodes, 1989-1991) |
 | Paul Lambert | ... | Hospital Board Member / ... (2 episodes, 1989-1991) |
 | Wayne Powers | ... | Jack Williams / ... (2 episodes, 1990-1992) |
 | Sherry Rooney | ... | Mrs. Plenn / ... (2 episodes, 1989-1991) |
 | Georg Olden | ... | Brad / ... (2 episodes, 1990) |
 | Mimi Savage | ... | Female Officer (2 episodes, 1992) |
 | Michael Bower | ... | Boy Nerd - Josh / ... (2 episodes, 1990-1991) |
 | Cynthia Mann | ... | Waitress (2 episodes, 1992) |

| Neil Flynn | ... | Policeman / ... (2 episodes, 1989) |
 | Max Supera | ... | Little Vinnie / ... (2 episodes, 1990-1992) |
 | Ursaline Bryant | ... | Group Leader (2 episodes, 1992) |
 | Stephanie Cambria | ... | Angela / ... (2 episodes, 1992) |
 | Jeremy Roberts | ... | Policeman / ... (2 episodes, 1989-1990) |
 | Alison Tucker | ... | Jamie / ... (2 episodes, 1990-1992) |

| Susan Krebs | ... | Dr. Pinkley (2 episodes, 1990) |
 | Kimberly Neville | ... | Liz / ... (2 episodes, 1991) |

| Bernie Hern | ... | Mr. Berman (2 episodes, 1989-1991) |
 | Ben Kronen | ... | Patient (2 episodes, 1990-1993) |

| Barry Livingston | ... | Bob / ... (2 episodes, 1990-1992) |
 | Gregg Marx | ... | Dr. Gary Russo (2 episodes, 1990-1992) |
 | Mark Sawyer | ... | 30's Him / ... (2 episodes, 1990-1992) |

| Angelo Tiffe | | (2 episodes, 1990-1992) |
 | Jay Gerber | ... | Dr. Greenburg (2 episodes, 1990-1991) |
 | Gloria Henry | ... | Irene O'Brien (2 episodes, 1990-1991) |
 | Stan Kamber | ... | Mr. Sullivan (2 episodes, 1990-1991) |
 | Tim O'Connor | ... | Don O'Brien (2 episodes, 1990-1991) |
 | Barry Michlin | ... | Dr. Kagan / ... (2 episodes, 1990) |
 | Al Septien | ... | Paramedic (2 episodes, 1990) |

| Richard Fancy | ... | Howard Stewart (2 episodes, 1991-1992) |

| Emily Kuroda | ... | Anesthesiologist / ... (2 episodes, 1991-1992) |
 | Elizabeth Norment | ... | Nancy Stewart (2 episodes, 1991-1992) |

| Perrey Reeves | | (2 episodes, 1991-1992) |

| Andrew Bilgore | ... | Aaron (2 episodes, 1991) |
 | Jeannie Elias | ... | Mrs. Stevens (2 episodes, 1991) |
 | S. Marc Jordan | ... | Mr. Jenkins (2 episodes, 1991) |
 | Justin Lord | ... | Dr. Owens (2 episodes, 1991) |

| James Morrison | ... | Mr. Stevens, father of Will (2 episodes, 1991) |

| Garette Ratliff Henson | ... | Will (2 episodes, 1991) |
 | Suzanne Tara | ... | Candystriper / ... (2 episodes, 1991) |

| Ray Abruzzo | | (2 episodes, 1992) |

| Katherine Cannon | ... | Dr. Julie Ross (2 episodes, 1992) |
 | Maggie Wheeler | ... | Dr. Spencer / ... (2 episodes, 1992) |
|
| Stephen Cragg | .... | supervising producer / co-executive producer (65 episodes, 1989-1993) |
| Joe Ann Fogle | .... | producer / co-producer / ... (65 episodes, 1989-1993) |
| Scott Goldstein | .... | producer / senior producer / ... (64 episodes, 1989-1993) |
| Mark Horowitz | .... | supervising associate producer / co-producer / ... (64 episodes, 1989-1993) |
| Linda Morris | .... | producer / supervising producer / ... (63 episodes, 1989-1993) |
| Vic Rauseo | .... | producer / supervising producer / ... (63 episodes, 1989-1993) |
| Jeffrey A. Henry | .... | associate producer / supervising associate producer (63 episodes, 1989-1992) |
| Steven Bochco | .... | executive producer (51 episodes, 1989-1991) |
| Phil Kellard | .... | producer / senior producer (50 episodes, 1989-1991) |
| Tom Moore | .... | producer / senior producer (50 episodes, 1989-1991) |
| Arturs Rusis | .... | associate producer (46 episodes, 1991-1993) |
| Nat Bernstein | .... | co-producer / producer / ... (40 episodes, 1990-1993) |
| Mitchel Katlin | .... | co-producer / producer / ... (39 episodes, 1990-1993) |
| Jill Gordon | .... | producer (19 episodes, 1989-1990) |
| Nick Harding | .... | co-producer / producer (15 episodes, 1991-1993) |
| Ron Mitchell | .... | coordinating producer (14 episodes, 1991-1993) |
| Hollis Rich | .... | co-producer (10 episodes, 1991-1992) |
| Elaine Aronson | .... | co-producer (2 episodes, 1992) |
| |
|
| Concetta Rinaldo-Williams | .... | second assistant director / first assistant director / ... (46 episodes, 1989-1992) |
| Jeffrey M. Ellis | .... | second assistant director (25 episodes, 1990-1991) |
| Irwin Marcus | .... | first assistant director (21 episodes, 1989-1991) |
| Danny Irom | .... | second assistant director (13 episodes, 1991-1992) |
| Charlotte Dreiman | .... | first assistant director (12 episodes, 1989-1990) |
| Edward Crocitto | .... | second second assistant director (10 episodes, 1989) |
| Dinah LeHoven | .... | dga trainee (9 episodes, 1990) |
| Kenneth J. Silverstein | .... | dga trainee (8 episodes, 1989-1990) |
| Judith Moore | .... | dga trainee (8 episodes, 1990-1991) |
| Jessica Kreps | .... | dga trainee (8 episodes, 1991) |
| Kimberly Law | .... | dga trainee (8 episodes, 1991) |
| Ronald Chong | .... | dga trainee (7 episodes, 1990) |
| Nancy Jacobs | .... | first assistant director (6 episodes, 1990-1992) |
| Mitchell Bock | .... | first assistant director (3 episodes, 1989) |
| Mark Tobey | .... | dga trainee (3 episodes, 1992) |
| |
|
| Nancy E. Wilkerson | .... | production coordinator (64 episodes, 1989-1992) |
| Barbara M. Kadell | .... | medical consultant (63 episodes, 1989-1992) |
| Susan Kinnevy | .... | assistant to producers (63 episodes, 1989-1992) |
| Gareth Wootton | .... | medical consultant (63 episodes, 1989-1992) |
| Linda Klein | .... | technical consultant (62 episodes, 1989-1992) |
| Jean Crupper | .... | assistant to producers (60 episodes, 1989-1992) |
| David E. Kelley | .... | creative consultant (60 episodes, 1989-1992) |
| Helene Davis | .... | assistant to producers / assistant to producer (50 episodes, 1989-1991) |
| Eileen Heisler | .... | assistant to producers (50 episodes, 1989-1991) |
| Barbara Kroells | .... | assistant to producers (50 episodes, 1989-1991) |
| Monique S. Salvato | .... | assistant to line producers / assistant to producers (46 episodes, 1991-1993) |
| Caroline James | .... | production accountant (45 episodes, 1990-1992) |
| Michael Mann | .... | location manager (42 episodes, 1990-1992) |
| Kathy Nakayama | .... | assistant to producers (38 episodes, 1990-1992) |
| Alvin Greenman | .... | script supervisor (26 episodes, 1989-1990) |
| Nat Bernstein | .... | story editor / executive story consultant (25 episodes, 1989-1990) |
| Mitchel Katlin | .... | story editor / executive story consultant (25 episodes, 1989-1990) |
| Rick Wallace | .... | executive consultant (25 episodes, 1989-1990) |
| Kathryn Davison | .... | assistant to producers (25 episodes, 1990-1991) |
| Nick Harding | .... | executive story editor / story editor (25 episodes, 1990-1991) |
| Meredith Underwood | .... | assistant to producers (25 episodes, 1990-1991) |
| Joanie Blum | .... | script supervisor (22 episodes, 1990-1991) |
| Antoinette Levine | .... | location manager (21 episodes, 1989-1990) |
| Candace Montgomery-Lira | .... | production accountant (17 episodes, 1989-1990) |
| Hollis Rich | .... | executive story editor (13 episodes, 1990-1991) |
| Debra J. Kleid | .... | assistant to producers (13 episodes, 1991-1992) |
| Allyson Rubin | .... | assistant to producers (13 episodes, 1991-1992) |
| Cynthia Ruble | .... | assistant to producers (13 episodes, 1991-1992) |
| Ellen Herman | .... | executive story editor (10 episodes, 1991-1992) |
| Todd Fischer | .... | production assistant / production coordinator (10 episodes, 1991) |
| Andrea Walzer | .... | script supervisor (9 episodes, 1991) |
| Michael Swerdlick | .... | story editor (6 episodes, 1990) |
| Faye Brenner | .... | script supervisor (3 episodes, 1991) |
| Lester Hoyle | .... | script supervisor (3 episodes, 1992) |
| Charles Montoya | .... | assistant production coordinator (3 episodes, 1992) |
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