A system for detecting unauthorized removal or tampering, said system comprising: an input device comprising tamper-response electronics and memory; a flexible circuit assembly (126; 200; 300) coupled between said input device and a structure to which the input device is mounted, said flexible circuit assembly (126; 200; 300) comprising: an outer layer (136; 204; 302); and characterised in that said flexible circuit assembly (126; 200; 300) further comprises: a first inner layer (138; 208; 304) disposed between said input device and said outer layer (136; 204; 302), said first inner layer (138; 208; 304) comprising at least one switch (134; 214; 314); a cable (128; 202; 310) coupled with said flexible circuit assembly (126; 200; 300) and operatively connected to said tamper-response electronics of said input device; wherein said outer layer (136; 204; 302) of said flexible circuit assembly (126; 200; 300) and said cable (128; 202; 310) comprise a first tamper-responsive conductor circuit (140; 148; 210; 212; 316); and wherein said at least one switch (134; 214; 326) and said first tamper-responsive conductor circuit (140; 148; 210; 212; 316) are in electrical communication with said tamper-response electronics via said cable (128; 202; 310). an input device comprising tamper-response electronics and memory; a flexible circuit assembly (126; 200; 300) coupled between said input device and a structure to which the input device is mounted, said flexible circuit assembly (126; 200; 300) comprising: an outer layer (136; 204; 302); and characterised in that said flexible circuit assembly (126; 200; 300) further comprises: a first inner layer (138; 208; 304) disposed between said input device and said outer layer (136; 204; 302), said first inner layer (138; 208; 304) comprising at least one switch (134; 214; 314); a cable (128; 202; 310) coupled with said flexible circuit assembly (126; 200; 300) and operatively connected to said tamper-response electronics of said input device; wherein said outer layer (136; 204; 302) of said flexible circuit assembly (126; 200; 300) and said cable (128; 202; 310) comprise a first tamper-responsive conductor circuit (140; 148; 210; 212; 316); and wherein said at least one switch (134; 214; 326) and said first tamper-responsive conductor circuit (140; 148; 210; 212; 316) are in electrical communication with said tamper-response electronics via said cable (128; 202; 310). a first inner layer (138; 208; 304) disposed between said input device and said outer layer (136; 204; 302), said first inner layer (138; 208; 304) comprising at least one switch (134; 214; 314); a cable (128; 202; 310) coupled with said flexible circuit assembly (126; 200; 300) and operatively connected to said tamper-response electronics of said input device; wherein said outer layer (136; 204; 302) of said flexible circuit assembly (126; 200; 300) and said cable (128; 202; 310) comprise a first tamper-responsive conductor circuit (140; 148; 210; 212; 316); and wherein said at least one switch (134; 214; 326) and said first tamper-responsive conductor circuit (140; 148; 210; 212; 316) are in electrical communication with said tamper-response electronics via said cable (128; 202; 310).