A method for controlling an exhaust gas aftertreatment system, wherein the exhaust gas aftertreatment system comprises - a first reducing agent dosing device; - a first selective catalytic reduction device arranged downstream of the first reducing agent dosing device; - a catalytic particulate filter arrangement arranged downstream of the first SCR device, wherein the catalytic particulate filter assembly comprises a catalysed particulate filter, or wherein the catalytic particulate filter assembly comprises an oxidation catalyst and a particulate filter arranged downstream of the oxidation catalyst; - a second reducing agent dosing device arranged downstream of the catalytic particulate filter arrangement; and - a second selective catalytic reduction device arranged downstream of the second reducing agent dosing device; and wherein the method comprises the steps of: - estimating future exhaust conditions based upon predicted vehicle operating conditions; - estimating a future NOx conversion demand based on the estimated future exhaust conditions; and - dosing a reducing agent from the first reducing agent dosing device at a rate based at least on the estimated future NOx conversion demand wherein the step of dosing a reducing agent from the first reducing agent dosing device at a rate based at least on the estimated future NOx conversion demand comprises: - comparing the estimated future NOx conversion demand with a predetermined first threshold limit for NOx conversion demand; and - dosing a reducing agent from the first reducing agent dosing device, wherein if the estimated future NOx conversion demand is within the first threshold limit then the reducing agent is dosed at a predetermined baseline rate; wherein the baseline rate is adapted to correspond to from 20% to 60% of estimated future NOx conversion demand; and if the estimated future NOx conversion demand is beyond the first threshold limit then the reducing agent is dosed at an adapted rate, wherein the adapted rate differs from the baseline rate. - a first reducing agent dosing device; - a first selective catalytic reduction device arranged downstream of the first reducing agent dosing device; - a catalytic particulate filter arrangement arranged downstream of the first SCR device, wherein the catalytic particulate filter assembly comprises a catalysed particulate filter, or wherein the catalytic particulate filter assembly comprises an oxidation catalyst and a particulate filter arranged downstream of the oxidation catalyst; - a second reducing agent dosing device arranged downstream of the catalytic particulate filter arrangement; and - a second selective catalytic reduction device arranged downstream of the second reducing agent dosing device; - estimating future exhaust conditions based upon predicted vehicle operating conditions; - estimating a future NOx conversion demand based on the estimated future exhaust conditions; and - dosing a reducing agent from the first reducing agent dosing device at a rate based at least on the estimated future NOx conversion demand - comparing the estimated future NOx conversion demand with a predetermined first threshold limit for NOx conversion demand; and - dosing a reducing agent from the first reducing agent dosing device, wherein if the estimated future NOx conversion demand is within the first threshold limit then the reducing agent is dosed at a predetermined baseline rate; wherein the baseline rate is adapted to correspond to from 20% to 60% of estimated future NOx conversion demand; and if the estimated future NOx conversion demand is beyond the first threshold limit then the reducing agent is dosed at an adapted rate, wherein the adapted rate differs from the baseline rate.