  We present the status of our study into the feasibility of estimating the
parameters of inflation from planned satellite observations of the anisotropy
of the cosmic microwave background (CMB).We describe a perturbative procedure
for studying inflation models with soft departures from scale free spectra and
find that in this case the parameters of inflation are likely to be well
determined. We also demonstrate that radical departures from scale free initial
perturbations with broad features in $k$-space can be be measured by Planck.
However, allowing for very fine features in $k$-space can very strongly
compromise the ability to measure cosmological parameters.
