Rosemary Bishop wrote to her parents about twice a week from Girton College and continued to write to them regularly for many years afterwards, especially while working in the USA for a time in the 1960s. The letters tend to become shorter and more sporadic in the later years. There are, however, some very specific gaps in the chronology, chiefly from September 1959 to August 1960 and from September 1960 to July 1962 inclusive: it has been presumed that these may have been periods when RB was either living at the family home in Leicester or was working close enough to home to visit at weekends. The letters then peter out almost completely after February 1970.