DataSet dsTrade = (DataSet)Session["dsTrade"]; if (this.cboAccount.SelectedValue.Length == 0) { this.cboAccount.SelectedValue = "0"; } this.cboAccount.BindingType = mmBindingType.None; dsTrade.Tables[0].Rows[0]["AccountID"] = int.Parse(this.cboAccount.SelectedValue);The above code is referencing a combo box on my form (cboAccount) that I load using similar methods as you mention below, namely, as postbacks to the server based on user actions on other controls. Eventually, the user will need to select one of the values. The reason I set the selected value to '0' is so the business rule will throw back an error stating that this value must be entered. The underlying table (or business object) is Trade and the column is AccountID.