(9) Employment and occupation are key elements in guaranteeing equal opportunities for all and contribute strongly to the full participation of citizens in economic, cultural and social life and to realising their potential. (10) On 29 June 2000 the Council adopted Directive 2000/43/EC(6) implementing the principle of equal treatment between persons irrespective of racial or ethnic origin. That Directive already provides protection against such discrimination in the field of employment and occupation. (11) Discrimination based on religion or belief, disability, age or sexual orientation may undermine the achievement of the objectives of the EC Treaty, in particular the attainment of a high level of employment and social protection, raising the standard of living and the quality of life, economic and social cohesion and solidarity, and the free movement of persons. (12) To this end, any direct or indirect discrimination based on religion or belief, disability, age or sexual orientation as regards the areas covered by this Directive should be prohibited throughout the Community. This prohibition of discrimination should also apply to nationals of third countries but does not cover differences of treatment based on nationality and is without prejudice to provisions governing the entry and residence of third-country nationals and their access to employment and occupation. (13) This Directive does not apply to social security and social protection schemes whose benefits are not treated as income within the meaning given to that term for the purpose of applying Article 141 of the EC Treaty, nor to any kind of payment by the State aimed at providing access to employment or maintaining employment. (14) This Directive shall be without prejudice to national provisions laying down retirement ages. (15) The appreciation of the facts from which it may be inferred that there has been direct or indirect discrimination is a matter for national judicial or other competent bodies, in accordance with rules of national law or practice. Such rules may provide, in particular, for indirect discrimination to be established by any means including on the basis of statistical evidence. (16) The provision of measures to accommodate the needs of disabled people at the workplace plays an important role in combating discrimination on grounds of disability. (17) This Directive does not require the recruitment, promotion, maintenance in employment or training of an individual who is not competent, capable and available to perform the essential functions of the post concerned or to undergo the relevant training, without prejudice to the obligation to provide reasonable accommodation for people with disabilities. (18) This Directive does not require, in particular, the armed forces and the police, prison or emergency services to recruit or maintain in employment persons who do not have the required capacity to carry out the range of functions that they may be called upon to perform with regard to the legitimate objective of preserving the operational capacity of those services. (19) Moreover, in order that the Member States may continue to safeguard the combat effectiveness of their armed forces, they may choose not to apply the provisions of this Directive concerning disability and age to all or part of their armed forces. The Member States which make that choice must define the scope of that derogation. (20) Appropriate measures should be provided, i.e. effective and practical measures to adapt the workplace to the disability, for example adapting premises and equipment, patterns of working time, the distribution of tasks or the provision of training or integration resources. (21) To determine whether the measures in question give rise to a disproportionate burden, account should be taken in particular of the financial and other costs entailed, the scale and financial resources of the organisation or undertaking and the possibility of obtaining public funding or any other assistance. (22) This Directive is without prejudice to national laws on marital status and the benefits dependent thereon. (23) In very limited circumstances, a difference of treatment may be justified where a characteristic related to religion or belief, disability, age or sexual orientation constitutes a genuine and determining occupational requirement, when the objective is legitimate and the requirement is proportionate. Such circumstances should be included in the information provided by the Member States to the Commission. (24) The European Union in its Declaration No 11 on the status of churches and non-confessional organisations, annexed to the Final Act of the Amsterdam Treaty, has explicitly recognised that it respects and does not prejudice the status under national law of churches and religious associations or communities in the Member States and that it equally respects the status of philosophical and nonconfessional organisations. With this in view, Member States may maintain or lay down specific provisions on genuine, legitimate and justified occupational requirements which might be required for carrying out an occupational activity.