Alliance HealthCare Services, Inc. is a provider of outpatient diagnostic imaging and radiation therapy services. The Company operates in two segments: Imaging (Radiology) and Radiation Oncology. Radiology segment consists of diagnostic imaging services, including MRI (magnetic resonance imaging), PET/CT (positron emission tomography–computed tomography) and other imaging services. The Company's radiology services include the use of its imaging systems, technologists to operate the systems, equipment maintenance and upgrades and management of day-to-day shared-service and fixed-site diagnostic imaging operations. Radiation Oncology segment consists of radiation oncology services, which is operated through the Company's wholly owned subsidiary, Alliance Oncology, LLC. The Company serves range of services for cancer patients covering initial consultation, preparation for treatment, simulation of treatment, actual radiation oncology delivery, therapy management and follow-up care.