Some embodiments include methods of forming structures. Spaced-apart features are formed which contain temperature-sensitive material. Liners are formed along sidewalls of the features under conditions which do not expose the temperature-sensitive material to a temperature exceeding 300° C. The liners extend along the temperature-sensitive material and narrow gaps between the spaced-apart features. The narrowed gaps are filled with flowable material which is cured under conditions that do not expose the temperature-sensitive material to a temperature exceeding 300° C. In some embodiments, the features contain memory cell regions over select device regions. The memory cell regions include first chalcogenide and the select device regions include second chalcogenide. The liners extend along and directly against the first and second chalcogenides.