The present invention relates to a puncture resistant sealable vapour barriersterilisation bag capable of withstandinga steam sterilisation process whilst providing an effective microbiologicalbarrier having a first sealable opening suitable forreceiving items to be sterilised and a second sealable opening adapted tocouple to a sterilisation conduit. A third sealable openingmay be provided in the bag to facilitate circulation within the bag via thesecond and third openings when the first opening issealed. The bag forms the means for sterilising an article(s) solely withinthe plastic bag in conjunction with a sterilisation servicessupply device. The bag is preferably formed of plastics. Preferably amultilayer construction including a puncture resistant outerlayer and a heat-sealable inner layer. The bag may include a covert markingtechnology and/or a readable unique identificationcode such as a tamper-resistant label applied to the bag to facilitateuniformity and traceability.