Penicheiro has played professional basketball since her young teens. She is a member of Portugal's national women's basketball team. In 1998, she joined the Monarchs as a rookie, finishing third in the rookie of the year award voting. She is a 4 time WNBA all star player. She has tied the WNBA's record with 16 assists in one game twice already. In 1999, she was selected as a WNBA first team player. This was also the year she set her WNBA high in points, with 27 against the Minnesota Lynx. In 2001, she was selected as a member of the WNBA's second team.
Penicheiro has a brother who plays professionally in the Portuguese basketball league and who, according to her, is a very good basketball player too.
She had, as of June 19, 2003, 1,027 career points in the WNBA; for an average of 6.8 per game, 1,121 assists; for a total of 7.5 per game, 615 rebounds; for a total of 4.1 per game, and 322 steals, for a total of 2.15 per game.