Haori kimono jackets are traditionally held closed by a single tie at centre front, called a haori himo. The himo is always bought separately from the haori and can be changed to suit the occasion. On men;s haori the himo is usually attached with hooks and simply unhooked at one side to open the haori, on women's haori the himo is tied with a much simpler knot and untied to open the haori. 

Men's haori vary in formality, the bigger and thicker it is, the more formal the occasion to which it may be worn. A very thick, white himo with fluffy tassels is the most formal.