A system characterised by being configured to gather data concerning usage of a publication (20; 40; 62; 100; 120; 140; 160; 300; 400) by an individual, exposure of the individual to predetermined products within a commercial establishment, and exposure of the individual to media data having an acoustic component, such as radio and television broadcasts, pre-recorded content and streaming media, the system comprising: a publication usage data producing system including: a piezoelectric transducer (44, 80, 104, 105) included in the publication, the piezoelectric transducer to produce, when deformed, data indicating usage of the publication and providing the data to a first wireless transmitter (28, 58, 84, 108, 109, 124, 132); and said first wireless transmitter (28, 58, 84, 108, 109, 124, 132) in or on the publication to communicate publication usage data concerning participant's usage of the publication by transmitting acoustic energy; a second transmitter (36, 40, 56, 70, 78, 886) in the commercial establishment to transmit an acoustic product signal containing product data of a product in the commercial establishment; a portable monitor (24; 200; 500; 1204) including: a microphone to gather acoustic media data, to detect the publication usage data and to receive the product signal; a first processor to: determine product exposure data based on the product data contained in the product signal; detect an ancillary code in the acoustic media data; and identify acoustic media exposure data based on the ancillary code; a transceiver to establish a wireless link to communicate the publication usage data, the product exposure data, and the acoustic media exposure data to a second processor; and an enclosure to house the microphone, the first processor, and the transceiver; and the second processor to store the received publication usage data, product exposure data, and acoustic media exposure data in one or more databases; wherein the system is configured to provide integrated data estimating exposure of the individuals to the products, media, and publications. a publication usage data producing system including: a piezoelectric transducer (44, 80, 104, 105) included in the publication, the piezoelectric transducer to produce, when deformed, data indicating usage of the publication and providing the data to a first wireless transmitter (28, 58, 84, 108, 109, 124, 132); and said first wireless transmitter (28, 58, 84, 108, 109, 124, 132) in or on the publication to communicate publication usage data concerning participant's usage of the publication by transmitting acoustic energy; a piezoelectric transducer (44, 80, 104, 105) included in the publication, the piezoelectric transducer to produce, when deformed, data indicating usage of the publication and providing the data to a first wireless transmitter (28, 58, 84, 108, 109, 124, 132); and said first wireless transmitter (28, 58, 84, 108, 109, 124, 132) in or on the publication to communicate publication usage data concerning participant's usage of the publication by transmitting acoustic energy; a second transmitter (36, 40, 56, 70, 78, 886) in the commercial establishment to transmit an acoustic product signal containing product data of a product in the commercial establishment; a portable monitor (24; 200; 500; 1204) including: a microphone to gather acoustic media data, to detect the publication usage data and to receive the product signal; a first processor to: determine product exposure data based on the product data contained in the product signal; detect an ancillary code in the acoustic media data; and identify acoustic media exposure data based on the ancillary code; a transceiver to establish a wireless link to communicate the publication usage data, the product exposure data, and the acoustic media exposure data to a second processor; and an enclosure to house the microphone, the first processor, and the transceiver; and a microphone to gather acoustic media data, to detect the publication usage data and to receive the product signal; a first processor to: determine product exposure data based on the product data contained in the product signal; detect an ancillary code in the acoustic media data; and identify acoustic media exposure data based on the ancillary code; determine product exposure data based on the product data contained in the product signal; detect an ancillary code in the acoustic media data; and identify acoustic media exposure data based on the ancillary code; a transceiver to establish a wireless link to communicate the publication usage data, the product exposure data, and the acoustic media exposure data to a second processor; and an enclosure to house the microphone, the first processor, and the transceiver; and the second processor to store the received publication usage data, product exposure data, and acoustic media exposure data in one or more databases; wherein the system is configured to provide integrated data estimating exposure of the individuals to the products, media, and publications.