Modern agricultural biotechnology methods have been used to develop new varieties of agronomically important crops with novel characteristics through the introduction of new genes. Examples of such crops include corn, cotton, soybean, canola, and potatoes, and rice and wheat are currently in development. The first characteristics that were engineered into crops were predominately designed to meet specific needs of growers, e.g., insect protection and herbicide tolerance. These crops were introduced throughout the 1990s in the United States and were rapidly accepted by growers in the United States as well as other parts of the world, notably Canada and Argentina (1). Although growers have generally viewed the technology in a positive light, as evidenced by the rapid increase in total acreage planted with agbiotech varieties, some have viewed these crops and the food fractions derived from them with concern. Much of the debate centers around the consumer's right to know when such products are present in foods, even though the commercial agbiotech products have been widely reviewed and found to be as safe as conventional varieties by regulatory authorities worldwide. The controversy that has surrounded agbiotech crops has prompted a number of areas, including the EU and Japan, to pass laws requiring foods containing agbiotech ingredients above specified threshold limits to be labeled to address the consumer's desire to be informed.Agbiotech crops are produced by introducing into plants novel bits of DNA that code for production of specific proteins that result in the expression of new characteristics. The new DNA and protein can be found to varying degrees in many parts of these plants, including seeds and grain and certain processed fractions and final foods prepared from them.Methods for detecting and measuring DNA and protein are available and are used extensively in medical diagnostics, but the task of analyzing the myriad of final food products in sufficient numbers to be anything more than spot checking is so overwhelming and costly that it is not practical. In fact, some food producers who are attempting to comply with regulations are struggling to source raw agricultural commodities of certified identity as an alternative to massive testing. This strategy has placed the burden of identification squarely on the shoulders of growers and the grain distribution and processing industries and has created a demand for reliable, validated methods of analysis.Companies developing agbiotech crops recognize the importance of making sure growers and distributors have tools to facilitate the marketing of their grains to meet regulatory and consumer needs. As part of a product stewardship effort designed to facilitate the appropriate use and sale of their products, Monsanto commissioned Strategic Diagnostics Inc. (SDI) to develop a test kit to detect and quantify the newly introduced protein in Monsanto's insect protected MON810 YieldGard corn. MON810 corn expresses the Cry1Ab insecticidal protein from Bacillus thuringiensis (Bt), and it is by far the most prevalent transgenic corn in commercial production today.Given the prevalence of MON810 in the market and the current lack of validated methods, it was important to validate the performance of the method and demonstrate the ability of the test to quantify MON810 grain in bulk samples at concentrations relevant to regulatory thresholds. The AACC Technical Committee for Biotechnology Methods, in collaboration with the Institute of Reference Materials and Measurements (IRMM) of the Joint Research Centre of the EU selected SDI's MON810 test method for the first AACC sponsored collaborative study. Forty laboratories from 20 countries (Table 1) participated in the study. The labs were chosen based on their familiarity with the test methodology and their expertise in the field of testing for agbiotech crops. Many of these labs play a key role in their respective countries by providing technical expertise and recommendations that influence policy decisions regarding foods and agbiotech crops.