Guest work on the NYC-filmed dramas "New York Undercover" (Fox) and "Law & Order" (NBC) marked the actor's entry into television work. The big screen called soon after, and turns in such independents as "Arresting Gena" and "Kirk and Kerry" (both 1997) resulted in a respectable amount of buzz. In 1997, Acevedo earned a Drama Desk Award nomination for his intense turn in the revival of Sam Shepard's edgy "Tooth of Crime,” then began his run on the brutal prison drama, "Oz" (HBO, 1997-2003) as Miguel Alvarez, a young street tough from a long line of incarcerated men whose vanity played a great role in his downfall. Mentally troubled as a result of his imprisonment and the death of his infant son, Alvarez cut his own face, though the long scar on his face detracted only slightly from his good looks. Internal battles within the drug running Latino prison gang and personal conflicts with the warden (Ernie Hudson) culminated in a prison break for Alvarez (a time off from the series during which the actor filmed his part in the 2001 HBO miniseries "Band of Brothers"), but before long he was back behind bars again. A deeply disturbed and remarkably compelling character, Alvarez was given life by Acevedo with a consistently courageous and emotionally true performance.

Acevedo’s supporting role in Terrence Malick's lyrical World War II drama "The Thin Red Line" (1998) earned him critical notice and a 1999 Alma Award for Outstanding Supporting Actor. In 2000, Acevedo increases his exposure with several roles, including a small part in the stock market drama "Boiler Room", a turn in the prison-set feature "The Visit" and a featured supporting role in the Jamie Foxx action vehicle "Bait.” The following year would see Acevedo return to World War II with his work in "Band of Brothers", a miniseries produced by "Saving Private Ryan" vets Steven Spielberg and Tom Hanks. He also had roles in two restaurant-centered independents. The straight-to-video romantic comedy "In the Weeds" (1999) featured the actor as a psycho chef, while "Dinner Rush" (2001) costarred Acevedo as the black sheep son whose gambling debts threaten to ruin his restaurant owner father's plans for expansion.

Returning to television, Acevedo made appearances in episodes of “Third Watch” (NBC, 1999-2005), “Law & Order: Special Victims Unit” (NBC, 1999- ) and “24” (Fox, 2001- ) before reprising his “SVU” character District Attorney Investigator Hector Salazar on the surprisingly short-lived “Law & Order: Trial By Jury” (NBC, 2004-05). After a not-so-prominent role as an anonymous sentry in “The New World” (2005) and an appearance on the hit series “Numb3rs” (CBS, 2004- ), Acevedo returned to regular series work with “The Black Donnellys” (NBC, 2006- ), writer-director Paul Haggis’ look at four Irish brothers (Jonathan Tucker, Thomas Guiry, Billy Lush and Michael Stahl David) rising up the ranks of the mob in Hell’s Kitchen, New York City. Acevedo played an aspiring rival mobster who is not afraid of putting his own interests above his loyalties.