**Question:** A 30-year-old male presents to the outpatient clinic with erectile dysfunction (ED). Basic screening evaluation is unremarkable. The next step in the evaluation/management should be:

A. Psychiatric evaluation
B. Vascular evaluation
C. Endocrinological evaluation
D. Urological evaluation

**Core Concept:** Erectile dysfunction (ED) is a common sexual dysfunction characterized by the inability to attain or maintain an erection sufficient for sexual activity. In most cases, ED is a non-specific symptom that may indicate underlying pathologies.

**Why the Correct Answer is Right:** The correct answer, D (Urological evaluation), is chosen because ED is a common urological symptom and can be caused by various urological conditions. These include Peyronie's disease, prostatic disorders, and urethral strictures, among others. Additionally, urological evaluation can help rule out conditions like diabetes, hypertension, and hypothyroidism, which can cause ED but are addressed in options C (Endocrinological evaluation) and B (Vascular evaluation).

**Why Each Wrong Option is Incorrect:**

A. Psychiatric evaluation (Option A): Although psychological factors can contribute to erectile dysfunction, the correct step is to rule out urological causes first, as they are more common.

B. Vascular evaluation (Option B): While ED can be caused by vascular problems, performing a vascular evaluation first might lead to missing urological causes. Focus on urological evaluation first.

C. Endocrinological evaluation (Option C): Although endocrinological disorders can cause ED, the correct step is to rule out urological and vascular causes first.

**Clinical Pearl:** A thorough evaluation for erectile dysfunction should include a combination of history, physical examination, and appropriate investigations based on the evaluation results. In the absence of a clear cause, consult a specialist (urologist) for further evaluation and management.