A fluid delivery device (310, 410, 450, 810, 910, 1510) for administering a first medicament and a second medicament comprising: a housing, a first reservoir within the housing and configured to contain the first medicament, a second reservoir different from the first reservoir within the housing and configured to contain the second medicament, and a device for conveying the medicaments to the patient, CHARACTERISED BY: a basal drive mechanism (46, 60, 346, 846) for providing a basal delivery of the first medicament, the basal drive mechanism being within the housing and having a hydraulic fluid reservoir (352, 1452); a first pump chamber in fluid communication with the hydraulic fluid reservoir (352, 1452) of the basal drive mechanism (46, 60, 346, 846) via a first flow restrictor (356, 357, 856), the first pump chamber being configured to engage the first reservoir to provide basal delivery of the first medicament during use; and a second pump chamber different from the first pump chamber in fluid communication with the hydraulic fluid reservoir (352, 1452) of the basal drive mechanism (46, 60, 346, 846) via a second flow restrictor (358, 858), the second, pump chamber being configured to engage the second reservoir to provide basal delivery of the second medicament during use. a housing, a first reservoir within the housing and configured to contain the first medicament, a second reservoir different from the first reservoir within the housing and configured to contain the second medicament, and a device for conveying the medicaments to the patient, CHARACTERISED BY: a basal drive mechanism (46, 60, 346, 846) for providing a basal delivery of the first medicament, the basal drive mechanism being within the housing and having a hydraulic fluid reservoir (352, 1452); a first pump chamber in fluid communication with the hydraulic fluid reservoir (352, 1452) of the basal drive mechanism (46, 60, 346, 846) via a first flow restrictor (356, 357, 856), the first pump chamber being configured to engage the first reservoir to provide basal delivery of the first medicament during use; and a second pump chamber different from the first pump chamber in fluid communication with the hydraulic fluid reservoir (352, 1452) of the basal drive mechanism (46, 60, 346, 846) via a second flow restrictor (358, 858), the second, pump chamber being configured to engage the second reservoir to provide basal delivery of the second medicament during use. a basal drive mechanism (46, 60, 346, 846) for providing a basal delivery of the first medicament, the basal drive mechanism being within the housing and having a hydraulic fluid reservoir (352, 1452); a first pump chamber in fluid communication with the hydraulic fluid reservoir (352, 1452) of the basal drive mechanism (46, 60, 346, 846) via a first flow restrictor (356, 357, 856), the first pump chamber being configured to engage the first reservoir to provide basal delivery of the first medicament during use; and a second pump chamber different from the first pump chamber in fluid communication with the hydraulic fluid reservoir (352, 1452) of the basal drive mechanism (46, 60, 346, 846) via a second flow restrictor (358, 858), the second, pump chamber being configured to engage the second reservoir to provide basal delivery of the second medicament during use.