Movie S1 - Live imaging of embryonic skin development.

Movie S2 - Live imaging of hair placode polarization.

Movie S3 - Region specific cell movements during placode polarization.

Movie S4 - Live imaging of tracked cells during placode polarization shows counter-rotational cell movements.

Movie S5 - Counter-rotational cell movements fail to occur in Vangl mutants.

Movie S6 - Counter-rotational cell movements occur in the direction of placode growth in Fz6 mutants.

Movie S7 - Rho kinase inhibitor blocks counter-rotational cell movements in mid-polarizing placodes.

Movie S8 - Shh mutant placodes undergo extensive but disorganized cell rearrangements.

Movie S9 - Counter-rotational cell flows within the placode polarize the dermal condensate.