Electronic transponders used on toll roads often reduce delays at toll facil- ities and sometimes offer customers a discount in the toll. Nonetheless, many people avoid using toll roads or acquiring electronic transponders. Their reasons include a dislike for toll roads based on a belief that roads should be a public good or on infrequent use of the roadway. Obtaining a transponder requires an application process and an initial prepayment of tolls as a minimum requirement. In worst cases, applications must be mailed (rather than obtained at a distribution center, online, or through a phone call), transponder deposits are demanded, and credit cards are required for automatic replenishment of tolls. In addition to the impedi- ment of submitting an application, at least 20% of U.S. households do not have a credit card, and 10% do not have a bank account; such households would essentially be barred from obtaining transponders from most U.S. toll authorities. This paper analyzes these barriers by presenting the costs and benefits of the various toll transponder “tags” available in the United States in addition to models of toll road corridor users. Results show that higher-income households are more likely to have transponders and to use toll roads frequently. Other demographic and trip characteristic vari- ables have less influence on toll road frequency choices but do influence transponder acquisition. Several agencies insist on large transponder deposits and initial prepayment amounts and require payment methods that are not available to a large percentage of the U.S. population. Environmental justice (EJ) affects toll roads in at least two ways. First, there are concerns about the alignment of roadways and whether new roadway constructions or modifications disproportionately displace low-income and minority residences and businesses. Second, there are significant concerns about access to these toll roads, the ability of individuals to take advantage of the many benefits of electronic tolling (possibly toll discounts; generally faster movement through the toll facility), and the hurdles involved in obtaining transponders. It is difficult to assess an individual or a demographic group’s ability to pay for a toll road, but electronic transponder applications can be examined to determine how expensive it is to open a toll road account. It is also important to relate quantitative correlations between income and other demographics with toll road and transponder use. OBJECTIVE This paper examines EJ and equity issues related to transponder own- ership and road pricing in two different ways. First, a current list of all U.S. Toll Authorities that utilize electronic tolling is provided, as are the benefits and costs associated with each authority and transpon- der type. Second, three different surveys of toll road corridor users are employed to show the relationships between toll road use, transponder use, and frequency of use with income and other demographics. MOTIVATION This paper is motivated by the author’s previous research quantify- ing the hurdle to obtaining an electronic transponder on the SR-91 Express Lanes in southern California (1). That case study showed the relationship between income, commute distance, gender, language, carpool behavior, and switching propensity with toll road use and fre- quency of use, conditionally and unconditionally, on owning a transponder. The paper concluded that using the toll road and own- ing a transponder had little to do with income but that more-frequent toll road users did have higher incomes. The paper also demonstrated that there was a hurdle associated with obtaining a transponder in that not using the toll road could be modeled differently from the ordered choices of sometimes and more frequently using the toll road. However, that paper did not consider the banking and credit card characteristics of potential roadway users and did not discuss the transponder application process in great detail. This paper includes surprising statistics regarding the percentage of U.S. households with one or more credit cards and the percentage without bank accounts. These statistics are described in conjunction with a review of the many start-up fees and the complicated process of obtaining a transponder in the United States. In addition to the expected concerns of road- way corridor users regarding tolls and privacy, and the monetary and application-related hassles of obtaining transponders (which may lead to individuals’ not acquiring transponders), a significant num- ber of potential users do not have the credit card and bank accounts required to obtain and benefit from electronic transponders. BACKGROUND The relationship between EJ and transportation has been receiving increasing attention in the form of handbooks and research reports addressing how transportation planners should be aware of EJ and how it affects transportation projects. Recent reports include Cairns et al. (2), Sánchez et al. (3), and Grauberger and Van Orden (4 ). In general, EJ advocates want assurances that transportation projects and facilities are equally available to all, including low-income groups, minority groups, and other disadvantaged groups such as older travelers and travelers with disabilities. Some of the available information related to EJ and toll roads refers to the location and alignment of toll roads (5 ). This paper Environmental Justice Issues Related to Transponder Ownership and Road Pricing Emily Parkany Department of Civil and Environmental Engineering, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085. 97 Transportation Research Record: Journal of the Transportation Research Board, No. 1932, Transportation Research Board of the National Academies, Washington, D.C., 2005, pp. 97–108.