This paper analyzes the difference between nun and ka from an interactional perspective in terms of the practice of giving distinct types of 'focus' to the referent they mark. From a conversation-analytic perspective, Kim's (1990) analysis that nun and ka index the speaker-relevant focus and the event-relevant focus respectively is further elaborated on, with systematic attention being paid to 'sequential,' rather than 'cognitive,' aspects of how the referent is highlighted in the context of dealing with the prior talk and projecting sequential trajectories that favor distinct types of uptake. Nun is shown to be embedded in the context where the speaker orients himself/herself to problematizing and counteracting the interlocutor's action in the prior context, with the consequence that the interlocutor is solicited to make a decision and take a position vis-a-vis the speaker's action, preferably in the direction of aligning with it. The upshot of the focus-giving practice involving nun is characterized as a process by which the speaker's display of subjective and evaluative stance indexed by nun is empirically grounded by facts putatively observed by the speaker. The use of ka, in contrast, does not necessitate such a process of modulating the speaker's subjectivity. The focus-giving practice involving ka is geared towards highlighting the referent per se, with any agenda it projectively proposes being limited to the factual import that the referent has towards the event/state of affairs it relates to. That the interlocutor orients to the ka-marked referent in such a straightforward and non-motivated fashion is demonstrated by his/her often successful attempt at collaborative completion of the ka-utterance in-progress.