A Retainer Agreement is a contract between a client and a service provider, often a lawyer or consultant, where the client pays a fee in advance for ongoing services. This agreement outlines the scope of work, payment terms, and duration of the relationship, ensuring both parties understand their responsibilities. Typically, the retainer fee secures the provider's availability and may cover specific tasks or hours of work. This arrangement benefits clients by providing access to professional services when needed, while service providers gain financial stability and a committed client base.