Contour and other layers not matching with basemap

[Ange]

I have added lidar data from Defra survey data services to GIS file but it doesn't line up with the basemap - see image field shapes show it's out by a considerable amount.  What's the fix?

Have also added SciMaps for connectivity and erosion, these also seem to be misaligned with the basemap.

Thanks

[George_Thompson]

My initial guess is a projection mis-match.

What is the projection of the contour data?

What is the projection of the basemaps?

[Ange]

Hi, 'the project' Not sure what this means.

[George_Thompson]

Sorry, that should have said "projection". I have updated the questions.

[Ange]

Relatively new to using GIS I'm still none the wiser on answering that

[clt_cabq]

maps use different systems for showing data relative to the world, it gets very complicated very quickly but you have to make sure the data in your either are all using the same system or that the different data layers have a system designed so the map can 'project' them on the fly to make them line up correctly. This is probably something you should read about here:

Coordinate systems and map projections