Some embodiments are directed to a compliance monitor for monitoring patient usage of a dry powder medicament delivery device, including a store of medicament housed within a main body portion, and a base portion which is rotatable with respect to the main body portion. The medicament delivery device also includes a medicament dispensing means for dispensing a dose of medicament into an inhalation chamber, a mouthpiece through which the dose of medicament may be inhaled by a user, and a replaceable cap. The compliance monitor includes a first portion for receiving and/or retaining the base portion of the medicament delivery device, and a second portion for releasably securing the medicament delivery device to the first portion. The arrangement and construction is such that the fitting of the second portion of the compliance monitor to the first portion of the compliance monitor does not include a screw fit.
