Sustainability refers to the environmental, economic, and socio-cultural aspects of tourism development. It means a balance must be established between these three aspects to guarantee its long-term sustainability. Sustainable tourism not only examines and responds to the needs of the present, but focuses on how current actions will also reduce negative impacts in the long term.

For that purpose, it should:
- Make optimal use of environmental resources that constitute a key element in tourism development, maintaining essential ecological processes and helping to conserve natural heritage and biodiversity.
- Respect the socio-cultural authenticity of host communities, conserve their built and living cultural heritage and traditional values, and contribute to inter-cultural understanding and tolerance.
- Ensure viable, long-term economic operations, including stable employment and income-earning opportunities and social services to host communities, and contributing to poverty alleviation.

Sustainable tourists face many responsibilities to reduce tourism's impact on communities, including:
- informing themselves of the culture, politics, and economy of the communities being visited.
- anticipating and respecting local cultures' expectations and assumptions.
- contributing to intercultural understanding and tolerance.
- supporting local economies by purchasing local goods and participating with small, local businesses.
- conserving resources by looking for businesses that are environmentally conscious, and by using the least possible amount of non-renewable resources.

The advantages of sustainable tourism are diverse. Amongst the most important, it:
- Is informative: Travelers not only learn about the destination, they learn how to help sustain its character while deepening their own travel experiences. Residents learn that the ordinary and familiar may be of interest and value to outsiders.
- Benefits residents: Travel businesses do their best to employ and train local people, buy local supplies, and use local services.
- Conserves resources: Environmentally aware travelers favor businesses that minimize pollution, waste, energy consumption, water usage, landscaping chemicals, and unnecessary nighttime lighting.
- Does not abuse its product: Businesses cooperate to sustain natural habitats, heritage sites, scenic appeal, and local culture.
- Respects local culture and tradition: Foreign visitors learn about and observe local etiquette. Residents learn how to deal with foreign expectations that may differ from their own.
- Strives for quality, not quantity: Communities measure tourism success not by sheer numbers of visitors, but by length of stay, money spent, and quality of experience.
- Means great trips: Satisfied, excited visitors bring new knowledge home and send friends off to experience the same thing - which provides continuing business for the destination.

To resume it all, sustainable tourism:
- Minimizes environmental impacts,
- Improves contribution to local sustainable development,
- Requires lowest possible consumption of non-renewable resources,
- Supports efforts to conserve the environment and well-being of local people,
- Contributes to biodiversity.