Public agencies and non-governmental organizations explore and adopt best practices when delivering health and human services. In these settings, the use of the terms "promising practices," "best practices," and "evidence-based practices" is common and often confusing as there is not a general consensus on what constitutes promising practices or best practices.
In this context, the use of the terms "best practices" and "evidence-based practices" are often used interchangeably. Evidence-based practices are methods or techniques that have documented outcomes and ability to replicate as key factors.

Since evidence of effectiveness, potential for taking the intervention to scale, and generalizing the results to other populations and settings are key factors for best practices, the manner in which a method or intervention becomes a best practice can take some time and effort.
The following illustrates differences between three levels of practice.

1) Research-validated best practice: a program, activity, or strategy that has the highest degree of proven effectiveness, supported by objective and comprehensive research and evaluation.
2) Field-tested best practice: a program, activity, or strategy that has been shown to work effectively and produce successful outcomes and is supported to some degree by subjective and objective data sources.
3) Promising practice: a program, activity, or strategy that has worked within one organization and shows promise during its early stages for becoming a best practice with long-term sustainable impact. A promising practice must have some objective basis for claiming effectiveness and must have the potential for replication among other organizations.

Adapted from Wikipedia, the free encyclopedia. Internet. Accessed on January 18, 2016.