A sequentially activated multi-diaphragm foam pump (206; 1100) for a foam dispenser comprising: a housing; a liquid pump portion secured to the housing, the liquid pump portion having a liquid inlet (352; 1102), a liquid inlet valve (316A; 1105), a liquid pump diaphragm (310A; 1106), a liquid outlet valve (323A; 1116), and a liquid outlet (309A; 1122); an air pump portion secured to the housing, the air pump portion having a first air inlet (424B; 1104), a first air inlet valve (316B; 1107), a first air pump diaphragm (310B; 1108) and a first air outlet (309B; 1123), a second air inlet (424C; 1104), a second air inlet valve (316C; 1107), a second air pump diaphragm (310C; 1108) and a second air outlet (309C; 1123); wherein the liquid pump diaphragm (310A; 1106), the first air pump diaphragm (310B; 1108) and the second air pump diaphragm (310C; 1108) are formed in a unitary resilient member; a mixing chamber (325; 1130) in fluid communication with the liquid outlet (309A; 1122), the first air outlet and the second air outlet; wherein the liquid pump diaphragm (310A; 1106), the first air pump diaphragm (310B; 1108), and the second air pump diaphragm (310C; 1108) operate in sequential order; wherein the liquid pump diaphragm (310A; 1106) pumps a shot of liquid into the mixing chamber (325; 1130); wherein the first air pump diaphragm (310B; 1108) pumps a shot of air into the mixing chamber (325; 1130) to mix with the liquid to form a liquid air mixture; and wherein the second air pump diaphragm (310C; 1108) pumps a shot of air into the mixing chamber to mix with the liquid air mixture to form a foamy mixture; and an outlet (350, 1114) for dispensing foam. a housing; a liquid pump portion secured to the housing, the liquid pump portion having a liquid inlet (352; 1102), a liquid inlet valve (316A; 1105), a liquid pump diaphragm (310A; 1106), a liquid outlet valve (323A; 1116), and a liquid outlet (309A; 1122); an air pump portion secured to the housing, the air pump portion having a first air inlet (424B; 1104), a first air inlet valve (316B; 1107), a first air pump diaphragm (310B; 1108) and a first air outlet (309B; 1123), a second air inlet (424C; 1104), a second air inlet valve (316C; 1107), a second air pump diaphragm (310C; 1108) and a second air outlet (309C; 1123); wherein the liquid pump diaphragm (310A; 1106), the first air pump diaphragm (310B; 1108) and the second air pump diaphragm (310C; 1108) are formed in a unitary resilient member; a mixing chamber (325; 1130) in fluid communication with the liquid outlet (309A; 1122), the first air outlet and the second air outlet; wherein the liquid pump diaphragm (310A; 1106), the first air pump diaphragm (310B; 1108), and the second air pump diaphragm (310C; 1108) operate in sequential order; wherein the liquid pump diaphragm (310A; 1106) pumps a shot of liquid into the mixing chamber (325; 1130); wherein the first air pump diaphragm (310B; 1108) pumps a shot of air into the mixing chamber (325; 1130) to mix with the liquid to form a liquid air mixture; and wherein the second air pump diaphragm (310C; 1108) pumps a shot of air into the mixing chamber to mix with the liquid air mixture to form a foamy mixture; and an outlet (350, 1114) for dispensing foam.