Section 1: Introduction 1 History of Thyroid 2 Anatomy of Thyroid Gland 3 Physiology of Thyroid Gland Section 2: Diagnosis of Thyroid Disorders 4 Laboratory Evaluation of Thyroid Functions 5 Thyroid Imaging From an Endocrinologist's Perspective 6 Nuclear Imaging in Thyroid Disorders 7 Fine Needle Aspiration in Thyroid Disease 7A Clinical Aspects 7B Pathology Aspects (Cytology and Histopathology) Section 3: Hypothyroidism 8 Clinical Manifestations of Thyroid Hormone Deficiency 9 Refractory Hypothyroidism 10 Hypothyroidism and Associated Comorbidities 11 Hypothyroidism and Pregnancy Section 4: Disorders of Thyroid Hormone Excess 12 Clinical Evaluation and Manifestations of Thyroid Hormone Excess 13 Management of Thyroid Hormone Excess 14 Rare Forms of Thyroid Hormone Excess 15 Thyroid-associated Orbitopathy 16 Thyroid Hormone Excess and Pregnancy Section 5: Thyroid Disorders in Children 17 Approach to Congenital Hypothyroidism 18 Hypothyroidism in Children 19 Hyperthyroidism in Children 20 Thyroid Nodules in Children Section 6: Thyroid Disorders in Special Situations 21 Subclinical Hypothyroidism 22 Thyroid and Reproduction 23 Thyroid and Obesity 24 Non-thyroidal Illness Syndrome 25 Drugs and other Substances Interfering with Thyroid Function 26 Thyroid Emergencies 27 Surgery in Thyroid Disorders Part 1: Differentiated Thyroid Cancers Part 2: Poorly Differentiated and Anaplastic Thyroid Carcinoma Section 7: Miscellaneous Thyroid Disorders 28 Sustaining Elimination of Iodine Deficiency Disorders in India 29 Thyroiditis 30 Simple or Nontoxic Goiter 31 Nodular Thyroid Disease 32 Thyroid Carcinoma 33 Thyroid and COVID-19 34 Thyroid and Bone 35 Thyroid Hormone Resistance 36 Environmental Thyroid Disruptors