The adverbial expression IN STEP means:
1) with the same rhythm as sb or sth:
The four soldiers walked in step down the road.
She’s dancing in step with the music.
He’s a really fast runner. It’s hard to run in step with him.
2) in accordance with sb or sth:
Monica is in step with other young mothers now. [she has the same problems, ideas, etc.]
Her clothes are never in step with latest trends, but she doesn’t care.
It was built in step with our best knowledge.
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