|Full name||Harold Wallace McDonald|
|Date of birth||7 September 1975|
|Place of birth||Heredia, Costa Rica|
|Height||1.75 m (5 ft 9 in)|
|Playing position||Rightback, Central midfielder|
|2002–2003||→ San Luis (loan)||29||(2)|
|2014-||Costa Rica U-20|
* Senior club appearances and goals counted for the domestic league only.
He started his career with Deportivo Saprissa, being part of their minor league system. After a season with Saprissa and then Belén, he was transferred alongside compatriot Jewisson Bennett to Zacatepec, of Mexico's professional football league. He then came back and signed with Saprissa's arch-rivals Alajuelense, earning a place in the starting line-up really quick and remained with the team for 7 years. From 2002, he spent a year on loan playing for San Luis in the Mexican Primera División  before making a second return to Alajuelense. He later withdraw a lawsuit against his club, after claiming part of the transfer fee paid by San Luis to Alajuelense. He would end up playing a total of 424 league games and 80 international games for Liga.
He made his senior debut for Costa Rica in a September 1995 friendly match against Jamaica and earned a total of 101 caps, scoring 3 goals. He represented his country in 28 FIFA World Cup qualification matches and played in the 2002 and 2006 FIFA World Cups. He also played at two Copa América tournaments, four CONCACAF Gold Cups and three UNCAF Nations Cups.
- Scores and results list. Costa Rica's goal tally first.
|1.||13 February 2000||Qualcomm Stadium, San Diego, USA||Canada||2–1||2–2||2000 CONCACAF Gold Cup|
|2.||4 February 2007||Estadio Alejandro Morera Soto, Alajuela, Costa Rica||Trinidad and Tobago||1–0||4–0||Friendly match|
|3.||16 February 2007||Estadio Cuscatlán, San Salvador, El Salvador||El Salvador||1–0||2–0||2007 UNCAF Nations Cup|
- Datos de Harold Harold Wallace Mc Donald - Nación (Spanish)
- Elías Aguilar ve con ilusión ser del club Zacatepec - Nación (Spanish)
- Tico Harold Wallace jugará en el futbol mexicano - Nación (Spanish)
- Aguilar, Alejandro (21 May 2006). "Hárold se llenó de fe" [Hárold was filled with faith] (in Spanish). Diario al Dia.
- Reclamo contra la Liga Wallace baja el tono - Nación (Spanish)
- Los caudillos de la alineación rojinegra - UNAFUT (Spanish)
- Liberia atrae a “grandes” - Al Día (Spanish)
- Wallace aún no da el paso al banquillo - Nación (Spanish)
- Harold Wallace – FIFA competition record
- Wallace llegará a 100 juegos - Nación (Spanish)
- Harold Wallace - Century of International Appearances - RSSSF
- "Semblanzas: Hárold Wallace MacDonald" [Portraits: Hárold Wallace MacDonald] (in Spanish). Diario al Dia. 21 May 2006.
- Selección Sub-20 Harold Wallace: ‘Ya se había acabado la empatía entre Ronald Mora y los jugadores’ - Al Día (Spanish)