The present invention relates to a method of isolating a nucleic acid molecule from a biological sample. More particularly, the present invention relates to a method of isolating a ribonucleic acid molecule from a biological sample. The method of the present invention is useful in a range of applications including, but not limited to, diagnostic applications and research and development applications, to the extent that the isolation of nucleic acid molecules, and in particular ribonucleic acid molecules, is required. Most particularly, the method of the present invention provides for the isolation of ribonucleic acid molecules which are suitable for analysis by reverse transcriptase-PCR.