There is disclosed a method of pre-treatment and staining, according to a protocol, of a biological sample disposed upon the surface of a carrier, the method comprising the step of recording at least one parameter relating to at least one protocol step in a non-volatile memory located either upon or within the carrier or a device incorporating the carrier. Also disclosed is a device comprising: a non-volatile memory; a surface of the device adapted to carry a biological sample; and communications means electrically coupled to the memory for enabling data transmission to or from an external apparatus. Also disclosed is a method of controlling processing of a biological sample disposed upon a carrier, comprising: providing, upon or within the carrier or an apparatus holding the carrier, a non-volatile memory having information relating to sample processing priority or protocol; reading the information; and scheduling the processing based upon the information.