You cannot file for Chapter 7 bankruptcy if you received a Chapter 7 or Chapter 13 discharge within the previous six years (unless you paid off at least 70% of your unsecured debts in the chapter 13 bankruptcy).  On the other hand, you can file for Chapter 13 bankruptcy at any time.
 

You have valuable non-exempt property you do not want to lose.
 

You are behind on your mortgage or car loan.  In Chapter 7, you have little protection from foreclosure or repossession of your property if you are behind on payments.  In Chapter 13, you can repay mortgage arrearage through your plan, and keep your home by making the future payments required under your mortgage loan contract.  For a vehicle, the entire loan can be restructured and paid through your Chapter 13 plan.
 

You have debts that are non-dischargeable in Chapter 7.
 

You have co-debtors on consumer loans.  In Chapter 7, the creditors will go after your co-debtors for payment if you do not pay them in full.  In Chapter 13, the creditors may not seek payment from your co-debtors for the duration of your case if your Chapter 13 plan provides for full payment of co-signed debts.
 

Your income is sufficient to pay some of your debts and Chapter 7 might be considered a substantial abuse of the bankruptcy laws.
 

Your debts include tax obligations.  Chapter 13 will protect you from collections by tax agencies such as the IRS and allow the repayment of tax obligations without interest or penalties.
 

You feel a moral obligation to repay that portion of your debts that you are able to.