Generally time slip romances - some set mostly in the past (following the "adventures" of a character from the present), others mostly in the present (following the "adventures" of a character from the past). A few are "Historicals (with a dash of paranormal)" [latter quoted from author's website]. One or two are straight historical romances.
Order - chronological [presumably of the setting in the past, or times of the person from the past] - inferred from author's website - [here]. (Feb. 2015)
A couple of the titles are in both series (e.g. Till There Was You and When I Fall in Love), but have been put in de Piaget, here, until can put in multiple series.