Born in Milwaukee, WI on Dec. 21, 1955, Jane Frances Kaczmarek was the oldest of four children born to Defense Department employee Edward Kaczmarek and his wife, Evelyn, a teacher. Initially intent on following in her mother’s footsteps, Kaczmarek enrolled at the University of Wisconsin-Madison in the mid-1970s to pursue a degree in education. There, she met a fellow student, a fledgling actor named Tony Shalhoub, who convinced her to give acting a try. She did, and the rest was history. After receiving her BFA in Theatre from U. of W.-M., Kaczmarek got serious about her acting and applied to the prestigious Yale School of Drama in New Haven, CT, where she was accepted. There, Kaczmarek reunited with her friend Shalhoub and became part of the school’s famed repertory company.

After a year or two of honing her acting chops on stage, Kaczmarek finally made the leap into television in 1982 with a role in "For Lovers Only," a failed pilot about a honeymoon resort that aired as an ABC TV-movie. The following year, however, Kaczmarek had better luck when she landed a recurring role as a nurse on the hit hospital drama, "St. Elsewhere" (NBC, 1982-88). That led to subsequent guest-star roles in episodes of the fluffy romantic caper series, "Remington Steele" (NBC, 1982-87) and "Scarecrow and Mrs. King" (CBS, 1983-87). That same year, Kaczmarek appeared on the big screen as the long-suffering wife of Fred Ward's haunted Vietnam vet in 1984’s "Uncommon Valor." Audiences would also get to see Kaczmarek deliver a well-deserved, reverberant slap to her unfaithful movie husband, Robert De Niro, in director Ulu Grosbard’s 1984 romance, "Falling in Love.” Though the film was predicted to be a big hit and should have marked Kaczmarek's breakthrough, little came of the box office misfire. A starring role in the cutesy critical failure, "The Heavenly Kid" (1985), did even less to launch her career.

Although she had already made the leap to features, the actress did not shy away from TV work. A wise decision, as it would later turn out being the medium made for her. In 1984 alone, Kaczmarek impressed with a supporting turn in the groundbreaking sexual abuse drama, "Something About Amelia" (ABC) and a co-starring role in a moving syndicated adaptation of O. Henry's "The Last Leaf.” The following year, Kaczmarek made her regular series debut on the critically praised, but short-lived drama, "Hometown" (CBS, 1985-86). Although the show failed to grab an audience and was subsequently cancelled, Kaczmarek did not stay down for long. Less than a year later, she reemerged with several new TV movie projects, including "The Right of the People" (ABC, 1987) and "The Christmas Gift" (CBS, 1986). The year 1987 also saw Kaczmarek landing a featured part in the glitzy, marathon-length miniseries, "I'll Take Manhattan" based on the novel by Judth Krantz.

Kaczmarek appeared in two films in 1988; first, the highly derivative body-switcheroo comedy "Vice Versa" starring Judd Reinhold and Fred Savage; second, the Dennis Quaid-Meg Ryan thriller remake, "D.O.A." She then made a triumphant, albeit short, return to the small screen as attorney Linda Bauer on the hard-hitting courtroom drama, "Equal Justice" (ABC, 1990-91). In 1993, the actress added a failed sitcom, "Big Wave Dave's" (CBS, 1993-94), to her list of short-lived series regular gigs. In 1994, between making guest-star appearances on the celebrated legal dramas "L.A. Law" (NBC, 1986-1994) and "Law & Order" (NBC, 1990- ), Kaczmarek returned to doing stage work. She wowed theatergoers with her award-winning performances in the riveting Holocaust drama, "Kindertransport" (1994, 1996), in which she portrayed a mother who sends her child to England to be saved from the Nazis. She then followed up in 1995 with the absurdist comedy "Raised in Captivity," playing a self-loathing psychologist.

Most people would remember her, though, as the tough, but friendly traffic cop who flirted with a speeding Kelsey Grammer in a 1996 episode of "Frasier" (NBC, 1993-2004). That same year, she also turned in a strong supporting performance in "The Chamber," the 1996 filmic adaptation of John Grisham’s runaway bestseller. Kaczmarek later revisited her wronged-wife roots in the independent drama, "Wildly Available" (1997), before playing the “real world” mom of Tobey Maguire and Reese Witherspoon’s characters in the charming fantasy, "Pleasantville" (1998). Finally, Kaczmarek closed out the decade with a recurring role as the confronted and conflicted birth mother of Felicity Porter’s best friend, Julie (Amy Jo Johnson) on the angst-ridden late 90’s drama, "Felicity" (WB, 1998-2002).

The year 2000 finally saw Kaczmarek striking mid-season gold, starring as the harried, edgy mother of four on the surprise hit sitcom, "Malcolm in the Middle." Touted as "The Simpsons" with real people, the show’s unnamed fictional family bucked all of the television norms: a father (Bryan Cranston) who did NOT know best, a mother who was not always sweet (or even fully dressed, for that matter) and a pack of kids who actually got into some serious troubles. Kaczmarek's take as the drill sergeant-like matriarch, Lois, was a particular highlight of the show and no doubt rang true to female viewers. Simultaneously manipulative and demanding, yet smotheringly affectionate and forgiving, Kaczmarek played Lois with nary a hint of the syrupy clichés that often characterized TV moms. The uncompromising character proved a good fit for the actress. Overwhelmingly popular, Kaczmarek received numerous SAG, Emmy and Golden Globe nominations for her role.

After a long and successful run on Fox, “Malcolm in the Middle” ended production in 2006. After that, Kaczmarek made a number of recurring guest appearances on the Ted Danson comedy series, “Help Me Help You” (CBS, 2006-) .