Burns' inspiration for this poem came when he ploughed up a mouse's nest while working on the farm. The mouse was chased away by Burns' godson.
John Steinbeck got the title of his novel, Of Mice and Men from this poem. It is one of Robert Burns most well-known poems. The line "The best laid schemes o' mice an' men, Gang aft a-gley" has become a popular proverb the world over.

To a mouse,

on turning her up in her nest with the plough

November, 1785

Wee, sleekit, cow'rin', tim'rous beastie,
O, what a panic's in thy breastie!
Thou need na start awa sae hasty,
Wi' bickering brattle!
I wad be laith to rin an' chase thee,
Wi' murd'ring pattle!

I'm truly sorry man's dominion
Has broken nature's social union,
An' justifies that ill opinion,
Which makes thee startle
At me, thy poor earth-born companion,
An' fellow-mortal!

I doubt na, whyles, but thou may thieve;
What then? poor beastie, thou maun live!
A daimen icker in a thrave
'S a sma' request:
I'll get a blessin' wi' the lave,
And never miss't!

Thy wee bit housie, too, in ruin;
Its silly wa's the win's are strewin'!
An' naething, now, to big a new ane,
O' foggage green!
An' bleak December's winds ensuin',
Baith snell and keen!

Thou saw the fields laid bare an' waste,
An' weary winter comin' fast,
An' cozie here, beneath the blast,
Thou thought to dwell,
'Till, crash! the cruel coulter past
Out thro' thy cell.

That wee bit heap o' leaves an' stibble,
Has cost thee mony a weary nibble!
Now thou's turn'd out, for a' thy trouble,
But house or hald,
To thole the winter's sleety dribble,
An' cranreuch cauld!

But, Mousie, thou art no thy lane,
In proving foresight may be vain:
The best laid schemes o' mice an' men,
Gang aft a-gley,
An' lea'e us nought but grief and pain,
For promis'd joy.

Still thou art blest, compar'd wi' me!
The present only toucheth thee:
But, Och! I backward cast my e'e,
On prospects drear!
An' forward, tho' I canna see,
I guess an' fear.

Here is a short glossary of some words and terms used in the poem:

bickering brattle - scampering away
A daimen icker - An corn ear found in twenty-four sheaves of grain
thrave - shock
pattle - plowshare
snell - bitter
thole - put up with
cranreuch - hoarfrost
Gang aft a-gley - often go awry