[2] He spent a winter in Japan during the Russo-Japanese War and returned with his dream clarified, having noticed how healthy infants were due to 12 to 18 months of breastfeeding.

[2] On his return he began to use his access as a Justice of the Peace to licensed baby-boarding homes where typical conditions moved him to establish such a boarding facility himself at his Karitane residence at the foot of Huriawa Peninsula.

[6] King's methods to teach mothers domestic hygiene and childcare were strongly promoted through his first book on mothercare, Feeding and Care of Baby, and via a network of specially trained Karitane nurses and a widely syndicated newspaper column, Our babies, written by King's wife Isabella.

Apart from nutrition, King's methods specifically emphasised regularity of feeding, sleeping and bowel movements, within a generally strict regimen supposed to build character by avoiding cuddling and other attention.

In 1914 the physician Agnes Elizabeth Lloyd Bennett publicly opposed his stance that higher education for women was detrimental to their maternal functions and hence to the human race.

[7] He also excited controversy during his efforts to export his methods to Australia, Canada and the United Kingdom, with particular debate associated with his views on infant feeding formulas.

Back in New Zealand, by 1921, King became Director of Child Welfare in the Department of Health and by 1925 also Inspector-General of Mental Hospitals.

[12] It featured, controversially, in the 2007 Channel 4 documentary series, Bringing Up Baby, which compared it with the 1960s Benjamin Spock and the 1970s Continuum concept.

In Australia a number of maternal childhood centres in the 20's, 30's, and 40's were named after Truby King such as Coburg and Dandenong (both in Melbourne).