I present an overview of my catalogue of Galactic supernova
remnants (SNRs), which currently contains 274 objects. The
selection effects that apply to the identification of SNRs are
discussed, and the limitations that they impose on statistical
studies. The selection effects mean that young but distance SNRs
(i.e. those with small angular sizes) are easily missed from
current catalogues. One such young but distant SNR which is known
is G1.9+0.3, and I will discuss some recent radio and X-ray
observations of this remnant, which show it is only 150 years old
at most, and is the youngest knowb Galactic SNR.