A method for the detection of one or more polynucleotide amplification products, the method comprising the steps of: a) providing one or more oligonucleotide primer groups, each group comprising one or more oligonucleotide primer sets, each set characterised by: i) a first oligonucleotide primer (forward primer) comprising a fluorescence cassette-specific portion and a 3' downstream target-specific portion; and ii) one or more target-specific oligonucleotide primers; wherein the oligonucleotide primers in a particular set are each suitable for hybridisation to a strand of a target polynucleotide to permit formation of an amplification product of the target polynucleotide in an isothermal polynucleotide amplification reaction; and wherein the first oligonucleotide primer of each set in the same group contains a fluorescence cassette-specific portion that is capable of hybridising to the complement of the fluorescence cassette-specific portion of the first oligonucleotide primer of any set in the same group; b) providing one or more cassette oligonucleotide sets, each set characterised by: i) a first cassette oligonucleotide labelled with a fluorescent moiety (donor moiety) and having a sequence that is capable of hybridisation to the complement of the fluorescence cassette-specific portion of the first oligonucleotide primer of any set in a given oligonucleotide primer group; and ii) a second cassette oligonucleotide labelled with an acceptor moiety (for example a quencher moiety); wherein the cassette oligonucleotides of each set hybridise to one another to form a fluorescent quenched pair; c) initiating an isothermal polynucleotide amplification reaction in the presence of a strand displacement DNA polymerase thereby generating (if the target polynucleotide is present) a complementary sequence to at least a portion of the relevant first oligonucleotide primer, such that the relevant second (acceptor, for example quencher, labelled) cassette oligonucleotide is less able to hybridise to the relevant first (fluorescently labelled) cassette oligonucleotide, whereby a signal is generated; and d) detecting the signal that is generated. a) providing one or more oligonucleotide primer groups, each group comprising one or more oligonucleotide primer sets, each set characterised by: i) a first oligonucleotide primer (forward primer) comprising a fluorescence cassette-specific portion and a 3' downstream target-specific portion; and ii) one or more target-specific oligonucleotide primers; wherein the oligonucleotide primers in a particular set are each suitable for hybridisation to a strand of a target polynucleotide to permit formation of an amplification product of the target polynucleotide in an isothermal polynucleotide amplification reaction; and wherein the first oligonucleotide primer of each set in the same group contains a fluorescence cassette-specific portion that is capable of hybridising to the complement of the fluorescence cassette-specific portion of the first oligonucleotide primer of any set in the same group; i) a first oligonucleotide primer (forward primer) comprising a fluorescence cassette-specific portion and a 3' downstream target-specific portion; and ii) one or more target-specific oligonucleotide primers; wherein the oligonucleotide primers in a particular set are each suitable for hybridisation to a strand of a target polynucleotide to permit formation of an amplification product of the target polynucleotide in an isothermal polynucleotide amplification reaction; and wherein the first oligonucleotide primer of each set in the same group contains a fluorescence cassette-specific portion that is capable of hybridising to the complement of the fluorescence cassette-specific portion of the first oligonucleotide primer of any set in the same group; b) providing one or more cassette oligonucleotide sets, each set characterised by: i) a first cassette oligonucleotide labelled with a fluorescent moiety (donor moiety) and having a sequence that is capable of hybridisation to the complement of the fluorescence cassette-specific portion of the first oligonucleotide primer of any set in a given oligonucleotide primer group; and ii) a second cassette oligonucleotide labelled with an acceptor moiety (for example a quencher moiety); wherein the cassette oligonucleotides of each set hybridise to one another to form a fluorescent quenched pair; i) a first cassette oligonucleotide labelled with a fluorescent moiety (donor moiety) and having a sequence that is capable of hybridisation to the complement of the fluorescence cassette-specific portion of the first oligonucleotide primer of any set in a given oligonucleotide primer group; and ii) a second cassette oligonucleotide labelled with an acceptor moiety (for example a quencher moiety); c) initiating an isothermal polynucleotide amplification reaction in the presence of a strand displacement DNA polymerase thereby generating (if the target polynucleotide is present) a complementary sequence to at least a portion of the relevant first oligonucleotide primer, such that the relevant second (acceptor, for example quencher, labelled) cassette oligonucleotide is less able to hybridise to the relevant first (fluorescently labelled) cassette oligonucleotide, whereby a signal is generated; and d) detecting the signal that is generated.