Kikuyu, Kiembu and Kimbeere are Bantu languages spoken in the Southern Mount Kenya region. Although they are classified as different languages, they are mutually intelligible. However, these languages have minor structural differences at the phonological and morphological levels but these do not imply the existence of different languages. This chapter will focus primarily on phonological differences and similarities and from this analysis build a case for the harmonization of the sound systems of the three codes. Kikuyu is the largest of the three codes, with at least five linguistically discernable dialects, namely Kindia, Gigichugu, Kimathira, the Southern and Northern dialects. This chapter proposes the establishment of harmonization of the codes at the sound level and a harmonized phoneme matrix for the three codes. In order to do this, it will be necessary to explore the various phonemes evident in each of them. The thesis of this chapter is that the three codes emanate from a single proto-language and that the phonological differences that are apparent are due to sound changes. Consequently, the various sounds differentiating words are not very different in terms of articulation.