Speech-language pathologists, often called speech therapists are autonomous professionals who possess detailed knowledge of normal development and disorders of communication and swallowing, as well as assessment and intervention in these areas.

Speech therapists not only help with articulation of sounds nor do they work only with children. The field is very broad. Professionals with expertise in speech-language pathology specialize in disorders of developmental language, which may include treatment of late speakers, prematurely born children or children with autism. It is possible to facilitate speech and language development of children as young as 12 months and make the most of the rapid brain development in early years of life. Speech-language pathologists may work with patients after traumatic brain injury or stroke to rehabilitate their lost communication skills. Children and adults with hearing disorders may also benefit from work with speech therapists on the development of listening skills.

Another area of expertise is treatment of fluency disorders (stuttering) or voice disorders. For example, professional voice users such as broadcasters or singers frequently seek the support of speech-language pathologists to restore and maintain vocal health. Lastly, speech therapists correct articulation, swallowing, and they may help with the selection and use of appropriate alternative and augmentative communication to individuals who cannot rely completely on verbal communication.   

Speech-language pathologists may work directly with clients or with their caregivers or others who frequently interact with them (e.g. relatives, professionals, colleagues, supportive personnel, etc.), in order to create environments that facilitate optimal communication and swallowing.