To; for; from the standpoint of — indicates evaluation or perspective of someone or something (e.g., 'for X, Y is important').
私にとって家族が一番大切だ。
Family is the most important thing to me.
学生にとってこの本は役に立つだろう。
This book will probably be useful for students.
彼にとっては簡単な問題だが、私には難しい。
For him it's an easy problem, but for me it's difficult.