English writer, known for Shakespear, written with her brother Charles (Lamb, Charles).

Born into a poor family, Mary Lamb received little formal education. From an early age she helped support the family by doing needlework. Her mother was an invalid, and for many years she was entirely dependent on Mary's care. On Sept. 22, 1796, in a fit of madness, Mary stabbed and killed her mother. It is believed that there was a hereditary strain of mental illness in the family and that Mary's illness was precipitated by overwork. She was declared temporarily insane and placed under the guardianship of her brother Charles. For the rest of her life Mary was subject to recurrent bouts of mental illness.

In 1807 Mary and Charles published Tales from Shakespear, a collection of prose adaptations of William Shakespeare's plays, intended for children. Mary wrote the preface and the 14 comedies and histories, and Charles contributed the 6 tragedies; only Charles's name, however, appeared on the title page. The book was successful, and it established Charles Lamb's literary reputation. In 1809 Charles and Mary published two collaborative works, Mrs. Leicester's School, a book of children's stories, and Poetry for Children.

After Charles's death, Mary's mental health deteriorated. She survived him by 13 years.