A fluid handling cassette comprising a mid-plate positioned between a first plate and a second plate, said plates having a length, a width and a plate thickness, a first side of the mid-plate opposing the first plate and a second side of the mid-pate opposing the second plate; the first plate spaced apart from the mid-plate defining a width of a first inter-plate space, and the second plate spaced apart from the mid-plate defining a width of a second inter-plate space; an edge of the cassette having a cassette thickness defined by the thickness of each plate plus the width of the first and second inter-plate spaces, and a face of the cassette being defined by the length and width of the first or second plate; wherein the fluid handling cassette is characterized by one or both of (a) and (b): a. the mid-plate comprising a pump station defined by a pump diaphragm and the first side of the mid-plate, said pump diaphragm seated against the first side of the midplate and having an excursion range defined by the width of the first inter-plate space; and a pump actuation channel running parallel to the face of the cassette in the first inter-plate space connecting a pump actuation chamber bounded by the first plate and the pump diaphragm with a cassette pump actuation port located within the first inter-plate space at a first edge of the cassette; b. the mid-plate comprising a valve station defined by a valve diaphragm and the first side of the mid-plate, said valve diaphragm seated against the first side of the midplate and having an excursion range defined by the width of the first inter-plate space; and a valve actuation channel running parallel to the face of the cassette in the first inter-plate space connecting a valve actuation chamber bounded by the first plate and the valve diaphragm with a cassette valve actuation port located within the first inter-plate space at a first edge of the cassette. the first plate spaced apart from the mid-plate defining a width of a first inter-plate space, and the second plate spaced apart from the mid-plate defining a width of a second inter-plate space; an edge of the cassette having a cassette thickness defined by the thickness of each plate plus the width of the first and second inter-plate spaces, and a face of the cassette being defined by the length and width of the first or second plate; wherein the fluid handling cassette is characterized by one or both of (a) and (b): a. the mid-plate comprising a pump station defined by a pump diaphragm and the first side of the mid-plate, said pump diaphragm seated against the first side of the midplate and having an excursion range defined by the width of the first inter-plate space; and a pump actuation channel running parallel to the face of the cassette in the first inter-plate space connecting a pump actuation chamber bounded by the first plate and the pump diaphragm with a cassette pump actuation port located within the first inter-plate space at a first edge of the cassette; b. the mid-plate comprising a valve station defined by a valve diaphragm and the first side of the mid-plate, said valve diaphragm seated against the first side of the midplate and having an excursion range defined by the width of the first inter-plate space; and a valve actuation channel running parallel to the face of the cassette in the first inter-plate space connecting a valve actuation chamber bounded by the first plate and the valve diaphragm with a cassette valve actuation port located within the first inter-plate space at a first edge of the cassette. a. the mid-plate comprising a pump station defined by a pump diaphragm and the first side of the mid-plate, said pump diaphragm seated against the first side of the midplate and having an excursion range defined by the width of the first inter-plate space; and a pump actuation channel running parallel to the face of the cassette in the first inter-plate space connecting a pump actuation chamber bounded by the first plate and the pump diaphragm with a cassette pump actuation port located within the first inter-plate space at a first edge of the cassette; b. the mid-plate comprising a valve station defined by a valve diaphragm and the first side of the mid-plate, said valve diaphragm seated against the first side of the midplate and having an excursion range defined by the width of the first inter-plate space; and a valve actuation channel running parallel to the face of the cassette in the first inter-plate space connecting a valve actuation chamber bounded by the first plate and the valve diaphragm with a cassette valve actuation port located within the first inter-plate space at a first edge of the cassette.