The book of Lamentations is very closely associated with the book of Jeremiah, as they both deal with the destruction of Jerusalem: Jeremiah as a prophetical warning, Lamentations as a lament after the fall. The poetry is important in interpreting the book as it highly corresponds to the message, which is that although the people have turned away from God, and have been punished as a result, they can still confess their sin, and receive His blessing once again.
Read more about the book here.
Words of Grace 
Oh, Pastor Terry, how I would like to backtrack several years, when I was involved in a small class studying Lamentations. We went word for word, and I suffered from severe depression; in fact, I dropped out without completing the study.
If you could have taught that class using your comments on Lamentations and pointing out that hope is the true message, we (all of us were similarly depressed) would have survived blessed.
Anne,
How I would have delighted to have been there then. Since I wasn’t, perhaps a meditation on a portion today will continue to encourage you — “The LORD is my portion,” says my soul, “Therefore I have hope in Him.” The LORD is good to those who wait for Him, To the person who seeks Him. It is good that he waits silently For the salvation of the LORD.” (Lam. 3:24–26)