Kinetochores must continuously associate with dynamic microtubule plus ends, as they oscillate along the mitotic spindle. The molecular basis for the kinetochore to track microtubule plus ends remains unresolved. In a recent study, we have shown an essential role of the formin mDia3 in stable kinetochore microtubule attachment and metaphase chromosome alignment. This function is attributable to EB1-binding by mDia3, for replacing endogenous mDia3 with an EB1-binding deficient mutant results in chromosome misalignment. EB1 specifically targets to attached, antipoleward kinetochores with polymerizing microtubules during chromosome oscillation. Therefore, we speculate that the mDai3-EB1-APC complex formation may relay EB1 microtubule plus end-tracking activity to the kinetochore.