After Ernest Young left the School, the position of Headmaster was filled for a short time by Edmund Lightly, the Senior Master and one of the first members of staff. Randall Williams, a Welshman, arrived with a kind nature and was quickly accepted by all those around him, a significant point after the personalities of his predecessors. His keynote in life seemed to be to try and help others where he could, and indeed this came to the fore quite early on. The Old Gaytonians Association had almost ceased to exist during the First World War, and he was one of those instrumental in getting it back on its feet. The early 1920's saw a need for the Association to establish its own headquarters, and when the new school pavilion was being considered, Randall offered to amend the plans to include another story to accommodate an H.Q. It was only because of a need for their own sports facilities that the Association declined.
Originally Harrow County had been a football school, but in 1922 he introduced Rugby to the timetable, it becoming the main winter sport from 1926. Another change he made was to reduce the number of houses to four, removing Grove and Stanmore. At the time the decision was met with some opposition, but later those moves became firm and well known points of the school. 1922 saw the first 'Gayton Fair', and 1935 the opening of the School Swimming Pool, while, inspired by Ernest Young's idea, he also initiated a fund to aid those wishing to attend university. This particular venture, although successful, ceased with the start of the Second World War.
During this time, Mr. Wiliams was often accompanied in School activities by his wife, who became affectionately known to all as 'Lady Alice'.
With the growth of numbers into the school in the 1920's and 30's, Mr. Williams looked forward to an expansion of the existing buildings. He fought for more facilities for 'manual training', and was rewarded when, in 1939 building work began only to stop later that year with the advent of war.
The strain of the war years took their toll on Mr. Williams, and in 1945 he announced that he was to leave at the end of the summer term. After doing so, he took up a new career as curate to the Rev. G H Wooley, VC, Vicar of Harrow on the Hill Parish Church. He had received his ordination as Deacon in 1943, (and served as Honorary Chaplain to the Schools ATC Squadron during the war), fulfilling a lifelong desire to enter the Church, and became a priest in 1944. He later became Vicar of Wisborough Green in Sussex, before moving on to become vicar of Whiteley Village.
The Guest of Honour at the 1939 Speech day was Ernest Young, and it fell to Arthur Purton, one of the first pupils of 1911 and founder member of the Old Gaytonians Association, to propose a vote of thanks. Randall Williams took him aside later and remarked quietly, "I know the School isn't what it was in your day, but I try hard to make it so." Upon his retirement, the 'Evening Standard' reported Randall Williams as saying that he looked forward to 15 years in his new job. He passed away 15 years later, on January 22nd 1960.
A memorial service, attended by many former staff and pupils, was held in the School hall on February 21st that year.