  In the framework of the next generation of Cherenkov telescopes, the
Cherenkov Telescope Array (CTA), NectarCAM is a camera designed for the medium
size telescopes covering the central energy range of 100 GeV to 30 TeV.
NectarCAM will be finely pixelated (~ 1800 pixels for a 8 degree field of view,
FoV) in order to image atmospheric Cherenkov showers by measuring the charge
deposited within a few nanoseconds time-window. It will have additional
features like the capacity to record the full waveform with GHz sampling for
every pixel and to measure event times with nanosecond accuracy. An array of a
few tens of medium size telescopes, equipped with NectarCAMs, will achieve up
to a factor of ten improvement in sensitivity over existing instruments in the
energy range of 100 GeV to 10 TeV. The camera is made of roughly 250
independent read-out modules, each composed of seven photo-multipliers, with
their associated high voltage base and control, a read-out board and a
multi-service backplane board. The read-out boards use NECTAr (New Electronics
for the Cherenkov Telescope Array) ASICs which have the dual functionality of
analogue memories and Analogue to Digital Converter (ADC). The camera trigger
to be used will be flexible so as to minimize the read-out dead-time of the
NECTAr chips. We present the camera concept and the design and tests of the
various subcomponents. The design includes the mechanical parts, the cooling of
the electronics, the readout, the data acquisition, the trigger, the monitoring
and services.
