Not only does the ADA affect a commercial entity in its employment practices involving employees with disabilities but it also bears on the commercial entityAca,!a,,cs relationship with its customers. Finally, the ADA must be taken into consideration when a commercial entity contemplates expansion of its facilities either through new construction or alteration of existing facilities. The purposes of the Americans with Disabilities Act (the "ADA") include the "elimination of discrimination against individuals with disabilities" and to provide "standards addressing discrimination against individuals with disabilities." The ADAAca,!a,,cs attempt to affect these purposes is threefold. First, the ADA restricts covered employers from discriminating against employees based upon the employeeAca,!a,,cs disability. Second, the ADA requires that individuals with disabilities be provided the same access to and enjoyment of public accommodations. Finally, the ADA implements standards for accessible design for public accommodations and commercial facilities. In the first respect, the ADA protects employees from being discriminated against by an employer based upon the employeeAca,!a,,cs disability. The anti-discrimination arm of the ADA, however, does not apply to each and every employer. Rather, to be subject to the ADA, the employer must employ 25 or more employees each working day for 20 or more calendar weeks in the current or preceding year. In other words, if a company employees 25 or more employees who work five days a week for more than 20 weeks in either the current year or the previous year, the employer is subject to the mandates of the ADA. An employer subject to the ADA is precluded from discriminating against "a qualified individual with a disability because of the disability." The fact that an employee has an impairment, even a medically diagnosed impairment, however, does not mean that the employee is considered disabled. Rather, an employee is considered disabled if he or she has an impairment that substantially limits life activities of the individual, "such as caring for oneself, performing manual tasks, walking, seeing, hearing, speaking, breathing, learning, and working." In the event an employee has a condition that substantially limits a life activity, the employer possesses a duty to accommodate the employeeAca,!a,,cs disability. Such accommodation generally can be achieved by modifying the work environment to allow the employee to perform the essential functions of the position. For example, making existing facilities accessible and usable by the employee with the disability, modifying work schedules, reassignment, and modifying equipment are all considered to be reasonable accommodations for an employer to consider when faced with an employee with a disability. Although an employer possesses a duty to provide an employee with a disability "reasonable" accommodation, an accommodation is not reasonable if the accommodation would inflict an undue hardship upon the employer. In instances where the employer would experience undue hardship, the employer is not required to accommodate the employeeAca,!a,,cs disability. Generally, an employer is not required to provide the disabled employee with an accommodation if such accommodation would be of significant difficulty or expense to the employer. In addition to protecting employees from discrimination by employers based upon a disability, the ADA protects all individuals from discrimination from the full and equal enjoyment of the public accommodations of covered entities based upon the individualAca,!a,,cs disability. The public accommodation arm of the ADA applies to various private entities, including insurance offices, places of lodging, food establishments, entertainment facilities, retail establishments, service establishments and recreational facilities. Unlike the anti-discrimination provision of the ADA, the public accommodation arm applies to all entities, public or private, that offer goods, services and accommodations to the public at-large regardless of the number of employees the entity employs. Essentially, the ADA requires covered entities to offer "full and equal enjoyment of the goods, services, facilities, privileges, advantages, or accommodations" to individuals with disabilities. In other words, a commercial entity must offer disabled individuals the same access to and enjoyment of the entityAca,!a,,cs accommodations. Similar to the ADAAca,!a,,ca requirements to accommodate an employeeAca,!a,,cs disability, the public accommodation arm of the ADA requires entities to make necessary modifications, provide auxiliary aids and services and remove barriers to allow an individual with a disability the opportunity to equally enjoy the entityAca,!a,,cs goods, services and facilities. In other words, a covered entity possesses the duty to take measures so that individuals with disabilities are not precluded from the full and equal enjoyment of the entityAca,!a,,cs goods and services. A covered entity, however, is not required to make such modifications to existing barriers if such modification would not be readily achievable. A modification is readily achievable if it is "easily accomplished and able to be carried out without much difficulty or expense." In addition to the public accommodation requirements of the ADA, the ADA implemented minimum standards for new construction or alteration of an entityAca,!a,,cs facilities. Generally, the ADA mandates that any new construction or the alteration of an existing facility be designed and constructed or altered in such manner that the new construction or alteration is readily accessible to and usable by individuals with disabilities. To that end, detailed and voluminous design standards for new construction or alteration of existing facilities have been created. The standards for new construction and alteration of existing facilities generally are applicable to all commercial entities regardless of the entityAca,!a,,cs size.