Alex Delaware is a literary character created by American writer Jonathan Kellerman. The Alex Delaware detective series begins with When the Bough Breaks, published in 1985. Delaware appears in 39 of Kellerman's popular murder mysteries. Kellerman set the series in Los Angeles. Delaware is a forensic psychologist, although Kellerman wrote a back story in which Delaware practiced as a child psychologist.

Delaware has a friend, Milo Sturgis, who is a gay LAPD detective. Delaware helps Sturgis in his investigations, and the detective, who eventually reaches the rank of lieutenant, appears in each book in the series. As the series progresses, Delaware's relationship with Robin Castagna evolves, despite two long separations, during which various other romantic interests are introduced. In some of the more recent books in the series, Detective Petra Connor, introduced in Kellerman's standalone novel Billy Straight, also makes an appearance.

Alex Delaware (born in 1951) is empathetic and caring with particular emphasis on his concern for children. In Alex Delaware, Kellerman draws a hero who appears to be "a levelheaded, appealingly thoughtful guy". Kellerman also provides Alex Delaware with a side-kick, LAPD detective Milo Sturgis, as is customary in the mystery genre. It is also revealed that his mother was a manic-depressive and his father a raging, physically abusive alcoholic. Kellerman also adds a girlfriend, Robin Castagna, and a French bulldog, which serve to emphasize Delaware's empathetic nature. In several novels, Alex and Robin break up. Alex begins dating Dr. Alison Gwynn, also a Ph.D., clinical psychologist, while Robin dates Tim Plachette, a voice coach.

Kellerman's characterization of Delaware is typical of the "Post-Modern Detective" whom Professor Dick Gibson defines as "often an untrained amateur ... often sensitive, caring, thoughtful and socially aware, and he is often from a traditionally noninvolved group." Kellerman characterizes Delaware as "sensitive, socially involved, loving and passionate about his patients and his family relationships and cynical only about 'bad guys.'" Additionally, Kellerman brings a professional "sophistication" to the series.

Delaware's friend Milo Sturgis, adds to the portrayal of the post-modern detective. As Gibson explains: "[The] other important male role is Milo, a career policeman, a big shambling bear of a man, but, in a stunning role reversal, he is gay." Milo, Gibson points out, "the gay cop all too often functions as the cavalry. Delaware as amateur Knight Errant often gets into horrendous nightmare difficulties."

In the American Psychological Association Patrick McGuire writes about Kellerman's characterization of Delaware: "Alex Delaware's style is unlike that of the typical hard-nosed private eye. He goes about his work by interacting sympathetically with the people he meets and by quiet, professional observation. Kellerman says an empathetic psychologist is an ideal model for a detective."

Some reviewers, however, have criticized the Delaware novels based on overly intricate plotting, too much description of unnecessary elements, and "formula characters."

Kellerman introduces Alex Delaware, Ph.D., in When the Bough Breaks. Kellerman characterizes Delaware as a successful (albeit retired) child psychologist suffering from burn-out after working on a case of systematic child molestation that culminates when the offender commits suicide in Delaware's office. Detective Milo Sturgis urges Delaware to come out of retirement and interview a seven-year-old child who may have witnessed a crime. Sturgis appoints Delaware as a "special consultant" to the Los Angeles Police Department. Kellerman's timing in this novel coincided with news stories about child abuse in child care facilities. The book was adapted as a 1986 film starring Ted Danson as Alex and Richard Masur as Milo.