Professor Seckl's clinical work focuses on endocrinology. He has particular expertise in disorders of the hypothalamus (notably diabetes insipidus), pituitary and adrenal glands and has an interest in the genetics and molecular basis of endocrine disorders.

In research, Professor Seckl has worked for 30 years on the hormonal underpinnings of stress, the role of glucocorticoid hormones and their metabolism in understanding how events before birth 'programme' the risks of later disorders of the brain and body, on new approaches to understand and treat age-associated disorders of memory and how glucocorticoid hormones may cause obesity and metabolic disease. More than 40 doctors and scientists have completed PhDs in his laboratory. He has written over 400 papers and is one of Scotland's most cited medical scientists. He has spoken widely at academic meeting, to the press and lay audiences.