It is the ability to adapt to external conditions, correctly build internal and external relations that today is able to bring a business to a higher level of effective and sustainable development. This is the main rationale for building partnerships that mobilize internal resources and create new opportunities for the benefit of all stakeholders. The transformation of business into an ecosystem, the use of the principles inherent in natural ecosystems is the best response to the challenges of modern socio-economic reality. The peculiarity of this stage of business development lies in the management of the organization as an element of the business ecosystem. The activities of business ecosystems are built on the basis of partnerships, which in this context have a number of features. The article examines the main types and aspects of business ecosystems, traces the stages of their formation, systematizes and reveals the features and basic principles of partnerships, based on which, within such systems, organizations may ensure their effective and sustainable development.