This paper examines (1) the developmental aspects of the frequency and a range of functions expressed by Turkish interactional discourse markers şey 'uh', yani 'I mean', and işte 'you know' in child speech (4-8year-olds), and (2) age and gender-related changes in the frequency and functional uses of these three DMs in the speeches of 84 Turkish speakers from four different age groups (4-8, 18-23, 33-50, and over 50year-olds). Except for the children, the analyses were conducted in two different corpora, spontaneous and planned speech. As a result, in child speech, a developmental pattern from local to global in the use of the DMs yani 'I mean', and işte 'you know' was observed. Similarly, the frequency of these two DMs increased with aging among the four age groups in spontaneous speech. However, in planned speech, it was the case for the DM işte 'you know' only. Over 50year-old men used şey 'uh' more frequently in their spontaneous speech compared to women, whereas 33-50year-old women produced more işte 'you know' in their planned speech than men. The frequencies of şey 'uh', yani 'I mean', and işte 'you know' were lower in the planned speech condition compared to the spontaneous speech condition in general. Core functions of the three Turkish DMs under focus were described by conducting further analyses. These analyses also revealed that although there are some patterns that apply to all or a group of the DMs under focus, different variables interact in complicated ways resulting in differences in the functional uses of şey 'uh', yani 'I mean', and işte 'you know' by males and females among different age groups in two different speech conditions.