I've compiled all episodes throughout the Frasier series that develop Niles and Daphne's relationship. For you, posterity! It's all for you!
Keep an eye out for my next Frasier-related post in which I cite all the times Chuck Lorre straight-up ripped-off Frasier for the Big Bang Theory.
S01: Ep03, Ep06, Ep17
S03: Ep05, Ep13
S04: Ep06 Ep21
S06: Ep13, Ep22
S07: Ep10, Ep11, Ep14, Ep22, Ep23, Ep24
S08: Ep01, Ep02, Ep03, Ep05, Ep19
S09: Ep12, Ep13, Ep15
S10: Ep01, Ep08,* Ep14, Ep24
S11: Ep01, Ep24
*Astounding foreshadowing here!
*Remember S02, Ep04?