For example you could have something like this on your SUMMARY sheet:
[TABLE="class: grid, width: 1000"]
<tbody>[TR]
[TD][/TD]
[TD]A[/TD]
[TD]B[/TD]
[TD]C[/TD]
[TD]D[/TD]
[TD]E[/TD]
[TD]F[/TD]
[TD]G[/TD]
[TD]H[/TD]
[TD]I[/TD]
[TD]J[/TD]
[TD]K[/TD]
[TD]L[/TD]
[TD]M[/TD]
[/TR]
[TR]
[TD]1[/TD]
[TD]SUMMARY[/TD]
[TD]Dept1[/TD]
[TD]Dept2[/TD]
[TD]Dept3[/TD]
[TD]Dept4[/TD]
[TD]Dept5[/TD]
[TD]Dept6[/TD]
[TD]Dept7[/TD]
[TD]Dept8[/TD]
[TD]Dept9[/TD]
[TD]Dept10[/TD]
[TD]Dept11[/TD]
[TD]TOTAL[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD]Travel[/TD]
[TD]59.99[/TD]
[TD]250.50[/TD]
[TD]29.99[/TD]
[TD]33.33[/TD]
[TD]355.00[/TD]
[TD]20.50[/TD]
[TD]495.00[/TD]
[TD]56.34[/TD]
[TD]414.40[/TD]
[TD]101.50[/TD]
[TD]29.40[/TD]
[TD]1845.95[/TD]
[/TR]
[TR]
[TD]3[/TD]
[TD]Food[/TD]
[TD]13.50[/TD]
[TD]4.99[/TD]
[TD]3.00[/TD]
[TD]28.20[/TD]
[TD]27.00[/TD]
[TD]2.50[/TD]
[TD]47.20[/TD]
[TD]560.50[/TD]
[TD]28.50[/TD]
[TD]99.00[/TD]
[TD]35.30[/TD]
[TD]849.69[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]Drink[/TD]
[TD]6.99[/TD]
[TD]0.00[/TD]
[TD]4.50[/TD]
[TD]16.10[/TD]
[TD]13.00[/TD]
[TD]3.58[/TD]
[TD]3.20[/TD]
[TD]292.00[/TD]
[TD]39.40[/TD]
[TD]97.52[/TD]
[TD]47.40[/TD]
[TD]523.69[/TD]
[/TR]
</tbody>[/TABLE]
Where B2 holds the formula that can be copied across to L4:
=INDIRECT(B$1&"!"&CELL("address",$B1))
Assuming here that Travel/Food/Drink costs appear in cells B1/B2/B3 cells respectively on the Dept No. worksheets - again this is due to the layout I have tested on. But this is to give an idea of what can be achieved with INDIRECT.